Okunoto Konro Medium Hibachi Grill Starter Set

Diatomaceous earth is a light, porous stone made of fossilised plankton from an ancient seabed, now mined from Japan's Noto Peninsula. Metal passes heat straight through; diatomite's open structure insulates, so the heat stays in the firebox, not out the sides. We've tested it: even with charcoal lit, the outside doesn't get that hot.

Charcoal cooks mostly by radiant heat, about 70 to 75% in Japanese lab studies. The honest trade-off: diatomite hates water, and it can crack if you drop it.

Yes. It's the same Kinka konro you'll see on MasterChef Australia, where a hibachi grill has been a regular since 2010.

It's also the same konro you'll find in Japanese restaurants, here and in Japan.

Most people should get a small one. You're usually eating other things too, so you don't need a huge batch of skewers at once, and a small konro used fully holds its heat much better than a big one running half empty. Cooking for a crowd now and then? We'd get two small ones, not one big one.

Our guide: Small for 2 to 4 people, Medium for 4 to 8, Large for 6 to 12 and Extra Large Wide for 8 to 14. For one or two at the table, the small tabletop hibachi suits 1 to 2 and the medium 2 to 4.

The grill itself doesn't smoke. A konro body is diatomaceous earth, which doesn't burn. Smoke comes from the charcoal and from the food.

Damp charcoal smokes and spits, so keep it dry. Binchotan is over 90% carbon, so it burns very cleanly, but like all charcoal it still gives off carbon monoxide. Vegetables hardly smoke at all; fat from meat dripping onto hot charcoal makes plenty, so with steak or yakitori some smoke is unavoidable. That's why outside is better, or right under a strong rangehood.

At home, outside is better. If you cook indoors, do it only right under a strong rangehood or exhaust, and a carbon monoxide alarm is a good idea.

Restaurants cook on these grills indoors, but under big commercial extraction hoods. Burning charcoal gives off carbon monoxide, which you can't see or smell, and NSW Health advises that charcoal barbecues are for outdoor use. Never use one in a closed room.

Use a chimney starter about half full; its upward airflow lights the charcoal evenly. When a third to half of the charcoal is glowing red, tip it into the konro, then add more once the first lot is going.

Binchotan is dense and slow to catch, so give yourself time and start well before you plan to cook. Heat it gently: rushing it makes it pop and spark, so keep your face back. Smaller pieces catch faster, and some cooks start with easier-lighting charcoal and add binchotan on top.

Fine cracks are normal. Most diatomite konro crack in their first few fires as the body heats and cools, and the metal band around the outside is there to hold it together, so keep cooking.

Stop using it if it wobbles, a piece comes loose, or a crack is wide enough for charcoal or ash to get out, because then it can't safely hold the fire. Cracks can't be glued.

If your konro arrives cracked, don't use it; contact us and we'll replace it.

No. Use ordinary charcoal as the fuel and add a thin layer of binchotan on top; that's enough for yakitori. You can of course burn binchotan on its own, it's just expensive.

Japan makes very little binchotan and supply keeps getting tighter; our own wholesale price is about two and a half times what it was a few years ago. It burns longer and hotter, and in our experience that gives yakitori a better finish, but a layer on top is enough. Save the leftovers in an extinguisher to use again.