On the Stove, Always Use a Heat Diffuser

2026-07-18

Clay pots almost never fail because they wore out. They fail because of heat — either too much of it in one spot, or too sudden a change. Both are easy to avoid. Always cook on a heat diffuser On a stove, thermal shock comes from direct burner heat. A gas flame licking the base delivers intense heat to a small patch almost instantly, and clay cannot carry that heat sideways the way metal does. So that patch expands hard while the clay an inch away is still cool — and it is that tension, not age or use, that cracks pots. A heat diffuser removes the direct contact altogether. The flame heats a metal plate, and the plate passes gentle, even heat to the whole base — the pot never meets the flame at all. A simple diffuser plate (a flat tawa works too) between burner and pot is the single best habit for making a clay pot last for years. Always start from cold. Set the pot on the diffuser before you light the burner, so the plate and the pot come up to temperature together. Never lower a cold pot onto an already-hot diffuser or a lit burner — that is thermal shock in a single move, and it is how most pots are lost. This is the kind of thing to look for: a heat distribution plate for gas stoves. Any similar diffuser plate will do — the point is simply to put a layer of metal between the flame and the clay. Avoid sudden temperature changes Clay expands and contracts as it heats and cools. Change that temperature too quickly, in either direction, and it will crack. So: - Start low, raise gradually. Give the pot a few minutes on low before you turn the heat up. - Never put a hot pot on a cold or wet surface. Use a wooden board, a trivet, or a folded cloth. - Never add cold water to a hot pot — or hot water to a cold one. - Don't go from fridge to flame. Let a refrigerated pot come to room temperature first. - Let it cool on its own. Never quench a hot pot under a running tap. Never heat a clay pot empty Always add your liquid, oil or food before the pot goes on the heat. An empty pot heats fast and unevenly, which is exactly the condition that cracks it. You need less heat than you think Clay holds heat remarkably well. Low to medium is plenty for most cooking, and your food will keep cooking gently after you switch the burner off. High heat gains you nothing and risks the pot. A note on induction Unglazed clay will not work on an induction hob on its own — there is no metal for the induction field to act on. If induction is your only stove, you will need an induction interface disc, which doubles as a heat diffuser. What about the microwave? A different mechanism entirely, and no diffuser needed. Microwaves heat the water in your food, not the clay itself, so a pot that isn't waterlogged barely warms — we ran ours empty for three minutes and it produced no heat at all. Reheating in clay is fine; just let a freshly soaked or washed pot dry first. Treat it gently on the stove, and the same pot will cook for your family for years. See also our posts on preparing a new pot and cleaning without soap.