Seasoning and using a donabe

Do you have to season a new donabe?

Yes, a new donabe gets seasoned once before you cook a real meal in it. The Japanese word is medome (目止め): you cook a thin rice porridge in the pot so the starch works into the clay. Nagatani-en, the Iga kiln, puts it simply: the starch from the rice fills the pot's fine pores and stops it leaking. It also makes the pot less likely to hold onto smells and stains later on.

Two things people get wrong here. A pot sold as heat-resistant still wants medome; being flameproof isn't the same as being sealed, and Nagatani-en says so directly. A few newer pots with a ceramic-treated interior genuinely don't need it, because the coating already does that job. So read whatever came in the box first. If the maker's own sheet says something different from anything below, the maker wins.

Most donabe you'll ever handle are Banko ware from Yokkaichi in Mie. About 80 per cent of all the donabe made in Japan come from that one area, and the clay itself is roughly 40 per cent petalite, a lithium mineral that copes with a live flame. Banko was designated a national traditional craft in 1979, which is part of why a clay pot can sit on a gas ring at all.

How do you season it?

You simmer a thin porridge in the pot until it thickens, let it cool down completely (at least an hour), then rinse it and dry it for a full day before the first real meal. The steps are below. Set aside an afternoon and the next day too, because most of the time is just waiting.

Use leftover cooked rice rather than raw grains. Nagatani-en is blunt about it: their Iga pots are made from coarse clay, so cooked rice is the only thing they'll sign off on. Raw rice takes too long to turn to starch, and water works into the body while you wait. Some makers, the Banko care page among them, use potato starch dissolved in boiling water instead. It works the same way.

The cooling is the step people rush. A hot pot carried straight to a cold sink can crack right there.

Can you use a donabe on induction?

Only if that particular pot was built for induction. Clay doesn't respond to an induction coil, so an ordinary donabe will just sit on the hob doing nothing. Panasonic's own cooktop FAQ says a clay pot works on induction only when its base is made from a material that reacts to it rather than plain ceramic. Their general test for whether a pot will work on an induction hob is whether a magnet sticks to the base, though that's aimed at ordinary metal cookware rather than donabe specifically, so it's a rough guide at best for a clay pot.

Tiger, who make the hobs, list two ways around it: either the pot has a heating element built into its base, or you sit an ordinary pot on a separate induction heat plate. Tiger also says plainly that most conventional donabe couldn't be used on induction at all.

On gas, or on a portable gas burner at the table, an ordinary donabe is exactly where it wants to be.

Never heat one empty. Nagatani-en allows dry heating only on models carrying their "empty-heating OK" mark; every other pot gets water or stock in it before the flame goes on. Wipe the outside dry before it meets heat, too: a wet base on a hot ring is how pots split.

One for Australians. From 1 January 2024, planning permits for new homes and residential subdivisions in Victoria connect to all-electric networks only. If you're cooking in a new build there, or in an apartment with an induction top, check the base of the pot before you commit.

Why did mine crack? Is crazing normal?

Crazing is normal. A crack that runs through the body is not, and that kind almost always comes from a sudden jump in temperature rather than age. The fine web of hairlines across the glaze has a name, kannyu (貫入). Nagatani-en's answer to this exact question is that these are natural cracks in the glaze layer and the pot is fine to keep using. The glaze and the clay under it shrink at slightly different rates, so the surface crazes. It tends to show up more the longer a pot lives.

A crack you can catch a fingernail in, or one that reaches the rim, is the other kind. Stop using that pot.

The Banko makers' care page names the two big causes: sudden temperature changes, and deep-frying, which the pot was never built for. To that, add what Nagatani-en's own sheet warns against separately: a wet base on a hot ring, plus an empty pot left on a live flame.

If an old pot starts weeping water through the base, you can just season it again. Same porridge, same cooling.

How do you wash and dry it?

Wash it by hand once it has cooled down, and don't leave it standing in water. Detergent on a sponge is fine (Nagatani-en says so directly), but don't leave the pot soaking with detergent in it, because the clay will drink it up.

Drying is the step that decides whether you still like your donabe in two years. Turn it upside down with the lid off, somewhere the air moves. Nagatani-en's own figure is five to eight hours. It will feel dry long before it actually is.

Storing it over summer: wrap the body and the lid separately in newspaper, sit the lid on top upside down, and keep it somewhere ventilated. Their care page warns against leaving a pot boxed up in cardboard for months, which is how mould gets in.

How I do it at home

My own habit, not a maker instruction. I season a new pot on a Sunday afternoon and leave it on the rack, upside down and lidless, until Tuesday. The pots I've seen ruined were nearly all put away a day early.