Ask Kenji Anything Recap: Tools, Woks, Knives, Stew, and Smoke Detectors (a.k.a. “Cooking Detectors”) (Patreon)

Thanks for joining in last week for my live AKA. If you want to submit quesitons or participate in the next one, head over to the Ask Kenji Anything chat, open to all Super Frienjis and Cookbook Club members!

Cutting Boards & Kitchen Tools

Q: Do you have strong feelings about types of wooden cutting boards?

Yeah. I love wooden cutting boards and I use them almost exclusively.

One of my first restaurant jobs was at Number Nine Park in Boston, and they had these beautiful Boos Block boards. At some point the health department decided plastic boards were “safer,” so the restaurant had to get rid of the wood ones, and I inherited a couple of gigantic boards. It turns out plastic boards aren’t actually safer—wood has natural antibacterial properties, and plastic sheds microplastics into your food.

So I’m firmly pro-wood. I keep one big board out all the time (it was a gift from my friend Nagi or Just One Cookbook, my favorite source for Japanese home cooking). It doesn’t fit in the sink, so I never soak it—I just scrub it down with soap and water. Then I keep a few smaller wooden boards around. I use the big one for vegetables and ready-to-eat stuff, and if I’m cutting meat I’ll put a smaller board on top.

Wood is self-healing, it’s nicer to cut on, and you don’t destroy your knives.

Q: How often do you oil your wooden cutting boards and utensils?

As needed.

I use Howard Butcher Block Conditioner. When a board is freshly oiled, water beads up on it. Over time, water starts soaking in and staining more easily—that’s when it’s time to re-oil. For me that’s a few times a year.

Once a board gets really beat up or stained, I’ll sand it. I’ve even trimmed and re-squared boards before. You can make a wooden cutting board basically brand new again. You can’t do that with plastic.

Q: What about titanium cutting boards?

Hard no. Same with glass or any really hard surface.

You want your knife to sink in just a little so you can finish a cut cleanly. On hard boards you’re much more likely to get things sliced most of the way through but still attached. That's how you get those "scallion caterpillars" where they're mostly cut through, but still attached where the knife meets the board. And you’ll dull your knives fast. Stick with wood.

Induction vs Gas Ranges

Q: We’re replacing our range and leaning toward induction. Thoughts?

For most Western-style cooking, induction is great. A good induction range gives you very even heat—often more even than gas—and it’s very responsive.

Gas still wins for a few things: wok cooking where flame matters for flavor, and cooking where you want direct flame (charring chiles, garlic, etc.).

Induction is better for indoor air quality, generally better environmentally, and modern ones let you set and hold temperatures in ways gas just can’t.

You do have to be a little more careful about scratching the surface, but I’m not precious about tools. Scratches mean you’re cooking.

Just make sure your cookware is induction-compatible, and that it makes good contact. Some older cast iron pans with little lips on the bottom don’t work great.

Wok Questions (It Was Wok O’Clock)

Q: Why do you use a portable gas burner for wok cooking?

Honestly, a portable butane burner often works better than a Western home gas range for wok cooking.

Even though they max out at around 15,000 BTU and home burners can get hotter, the flame in a butane burner is very concentrated and aimed at the center of the wok. Western gas ranges are designed to spread heat evenly, which is great for flat skillets but inefficient for woks—most of the heat just flows up the sides.

If you’re looking for one, search for a portable butane burner around 15,000 BTU. There are good ones from Iwatani and others. I use a burner from BALMUDA, but it's currently only available in Japan. You can use any butane burner outdoors, or even set them on top of your stove under a hood. You can find a link to the Iwatani model, available for worldwide shipping, here on my shop page.

Q: Is The Wok useful if I’m cooking in a Western skillet?

Yes. There’s a whole section in the book on cooking in Western skillets!

A skillet won’t do everything a wok does—especially tossing and evaporation—but there are lots of homestyle dishes that work great in a skillet. You can absolutely cook good food that way. You can get signed and personalized copies of The Wok right here.

Q: What’s the best way to clean a wok when food is really burned on?

Heat it up, add water, and scrub. That’s how it’s done in restaurants.

A bamboo wok brush works great, but any reasonable scrubber is fine. It won’t damage the wok.

Also, with woks, seasoning is different than cast iron skillets. You’re not really building up thick polymer layers. Between uneven heat and frequent deglazing with soy sauce, wine, and acidic ingredients, that seasoning comes and goes. Don’t stress about accidentally scrubbing it off—just keep cooking.

Q: I’m intimidated by wok cooking. Any advice?

Not all wok cooking is high heat and fast! That’s a misconception.

Mapo tofu, curries, braises—lots of wok dishes don’t require screaming heat. If you’re nervous about spending money, don’t start with an expensive wok. Go to an Asian market or restaurant supply store and buy a 14-inch flat-bottom carbon steel wok. It’ll be cheaper and totally capable.

If you end up loving wok cooking and want something lower-maintenance later, you can always upgrade to something like my Super-Nitrided wok from Our Place, which will make cooking and cleaning easier.

Stocks & Broths

Q: I’ve got pork trotters, neck, and marrow bones. Should I roast everything?

Trotters are great for collagen, but they’re not the tastiest part of the pig.

For a really good pork stock, I’d use other pork bones too—ideally with some meat attached. If you want roasted flavor, roast the bones and vegetables, but add the trotters raw. Adding them raw maximizes gelatin extraction. Roasting trotters first means you lose some of that gelatin.

That collagen will add body to your stock, giving it a rich mouthfeel while still maintaining a nice clean flavor. A great stock should set like Jell-O when chilled.

Carryover Cooking

Q: My steaks overshoot way past my target temperature. What controls carryover?

A lot of things.

Mass matters. Cooking temperature matters. Fat matters. The hotter you cook, the bigger the temperature gradient inside the meat, and the more carryover you’ll get.

If your steaks consistently overshoot when you pull at 120°F, just pull them at 115 or 110. Cooking is contextual—adapt to your equipment and your results.

Fancy multi-sensor thermometers like the Predictive Thermometer from Combustion, Inc. can help predict carryover, but also: don’t let a number ruin dinner. Use a thermometer, but trust your tongue and your nose, not the number on the digital screen.

Stews, Braises, and Meat Texture (a.k.a. “Why Is This Tough?”)

Q: I made your beef stew and the meat didn’t come out super tender. How can I tell undercooked from overcooked meat in a stew?

This is a really good question, and it’s one of those things that’s genuinely unintuitive when you’re learning to cook.

I think a lot of us grow up with the idea that “longer cooking = more tender,” especially when it comes to stews and braises. And that’s only sort of true, and only up to a point.

When you’re braising a tough cut of meat—beef chuck, lamb shoulder, pork shoulder—what you’re really trying to do is break down connective tissue. That connective tissue is collagen, and as it cooks slowly in the presence of moisture, it converts into gelatin. That’s what gives you tenderness and that rich, silky mouthfeel.

But there are stages to this breakdown.

At first, the meat is just tough. The connective tissue hasn’t broken down yet, so when you bite into it, it feels chewy or resistant. If your stew meat is tough in that way, it almost always means it needs more time, not less.

Then there’s a sweet spot. The collagen has mostly converted to gelatin, the meat offers just a little resistance, and when you bite into it, juice comes out slowly. The fibers are still holding together, but they’re relaxed. This is where you want to be for most stews and braises.

After that, though, there’s another stage that people don’t always realize exists. The connective tissue that holds the individual muscle fibers together starts to break down too. Instead of a cohesive chunk of meat, the meat starts shredding very easily. For some dishes—things like carnitas, ropa vieja, pulled pork—that’s actually what you want.

And then beyond that, there’s a final stage that you really don’t want to hit. The muscle fibers themselves start to dry out and collapse. The meat doesn’t feel juicy anymore—it feels chalky or papery. When you bite into it, instead of juice slowly releasing, it kind of wrings out like a sponge. That’s overcooked stew meat.

So:

Too tough and chewy → undercooked, needs more time

Dry, mushy, or chalky → overcooked

Tender but still juicy → the window you’re aiming for

The frustrating thing is that this window can be surprisingly narrow, and it depends a lot on the cut of meat, the size of the pieces, and how hot your stew is simmering.

One other thing to keep in mind: not all meat is created equal. If you’re working with a cut that’s very lean or from an older animal, it may never hit that perfect window in quite the same way. Beef chuck, pork shoulder, lamb shoulder—those are forgiving cuts with lots of connective tissue. They give you some margin for error.

If you want more detail, I wrote an article about this for The New York Times (paywall) as well as for Serious Eats (free).

You can get my beef stew recipe in the desicription of this video demonstration.

Q: That beef stew recipe calls for Marmite for umami. Can I substitute fish sauce?

Yes, absolutely.

First off, you don’t need any added umami source at all. Beef has plenty of natural glutamates, especially if you’re browning it well at the beginning. A good sear does a lot of heavy lifting.

Things like Marmite, soy sauce, fish sauce, or straight-up MSG are really just little flavor nudges. They don’t make the stew “beefier” so much as they help round things out and make the savory flavors feel more complete.

If you don’t have Marmite, fish sauce works great. Soy sauce works great. MSG works great.

What I often like to do is use small amounts of a couple of different things rather than a larger amount of one. That way you get an overall umami boost without the stew tasting specifically like Marmite or fish sauce.

Knife Sharpening (Regular-People Edition)

Q: What’s the best knife sharpening strategy for normal folks?

The easiest answer is: take your knife to someone who knows what they’re doing.

A lot of farmers markets have mobile knife sharpeners now, and for most people, that’s going to be the lowest-friction, highest-reward option. You hand them your knives, you get them back sharp.

The one downside is that many of these services use electric grinding wheels. They’ll get your knife very sharp, but they also remove more material than is strictly necessary, which means your knife slowly gets shorter over time.

If you’re willing to learn a skill—and I genuinely think it’s a nice one to have—water stones are the way to go. You soak them, you start with a coarser grit, and you work your way up. It’s repetitive, a little meditative, and honestly kind of nice. I usually do it while watching TV.

Here's a video showing how I personally do it.

And if you want to see awkard baby Kenji demonstrating knife sharpening at American's Test Kitchen from nearly 20 years ago, you can see that here. (Note, in that video I was toeing the Cook's Illustrated line and promoting the use of an electric sharpener. I personally do not recommend them.)

What I would avoid at home are electric pull-through grinders. They’re fast, but they’re extremely aggressive, and they tend to chew through knives.

If you’re ever stuck in an Airbnb with a terrible knife, the unglazed bottom ring of a ceramic mug or bowl actually works surprisingly well as a makeshift sharpener.

Q: Honing vs. sharpening—what’s the difference?

Sharpening removes material. You’re creating a new edge.

Honing doesn’t really remove material—it straightens the edge. Over time, the very edge of a knife gets microscopically bent or kinked. A honing rod pushes it back into alignment so the knife feels sharp again.

One important note: honing rods are generally not a great idea for very hard steels. With very hard knives, you’re more likely to chip the edge than help it.

Cooking With Kids (and Reality)

Q: My four-year-old only eats a very short list of foods. How do you deal with that?

This is extremely normal, and also extremely frustrating.

Most of the research—and honestly, my experience—suggests that forcing kids to eat things they don’t want to eat backfires. It tends to make them more resistant and more anxious about food in the long run.

What we try to do is keep offering a wide range of foods, keep the experience positive, and not make food a battleground.

One thing that’s helped is framing things as “I don’t like this right now” instead of “I don’t like this.” Kids’ tastes change constantly, and they already have evidence that their tastes have changed in the past.

We also don’t keep every preferred food in the house. If it’s not there, it’s not an option.

And if a meal isn’t eaten and a snack is requested later, that meal becomes the snack. Kids are clever, and they will absolutely test the system if you let them.

High Heat, Smoke, and the Way Restaurants Work

Q: What’s it like cooking with very high heat in a commercial kitchen?

It’s hot. Like, really hot.

When you’re working the line, the ambient temperature behind the stoves can easily be 100–120°F. You sweat constantly. You drink tons of water. You don’t pee much because you’re sweating it all out.

From a cooking standpoint, the biggest difference is how high heat changes the physics of what’s happening in the pan. Liquids evaporate faster. Bubbling is more vigorous. Emulsions form more easily. Reductions happen quickly.

That’s why restaurant vegetables can be bright green, perfectly tender, and coated in a glossy butter-and-stock glaze. The glaze forms fast enough that the vegetables don’t have time to overcook.

At home, you can get similar results, but it usually takes more shaking, more whisking, and more patience.

Q: How do you deal with smoke in small kitchens?

Best case scenario is a hood that actually vents outside.

If you don’t have that—and many apartments don’t—you open windows, use fans, and try to move air as best you can. Sometimes you just accept that it’s going to be smoky.

Dave Arnold calls smoke detectors “cooking detectors,” which feels about right.

Q: Any update on the halal cart chicken and rice?

I've been working on an update of my Halal Cart Chicken and Rice recipe, originally publised on Serious Eats and one of my most popular recipes of all time. The update is coming soon—probably six or seven weeks out.

There are a few improvements. The rice is better, the process is different, and we’re also treating it as a blueprint rather than just a single recipe. Once you understand the structure, you can spin it into a lot of different meals. Think: Lemongrass chicken with coconut rice. Chicken with ras-el-hanout and chickpeas. Masala chicken with buttery lentils and kachumber. Chicken adobada with green rice, and so on. The same basic process, but adapted into widely ranging flavors. This is part of the premise of the book I'm currently working on. Learning these core techniques that can then be applied across a wide range of flavors and ingredients to allow you to adapt your cooking to suit your own taste.

The updated base recipe will be publicly available and free, while the variations will be part of the Cookbook Club tier.