Dum Cooking: How to Seal and Slow-Steam a Pot

What dum means

Dum (from the Persian for “breath”) is the technique of cooking food in a tightly sealed pot over very low heat, so it finishes in its own trapped steam. Nothing escapes: not moisture, not aroma. It’s how biryani rice turns long, separate and fragrant, how a qorma’s flavours deepen, and how a pulao absorbs every bit of its stock. The method came to South Asia through the Mughal kitchens, and the same idea lives on in Persian rice dishes and Arab mandi.

Why it works

When a pot is sealed, the steam inside can’t escape, so the temperature stays steady and the moisture keeps circulating. Rice that went in three-quarters cooked absorbs the steam and finishes gently, without breaking. Meat at the bottom of a kachchi biryani cooks in its own juices. Saffron, kewra, mint and fried onions on top perfume everything below.

How to seal a pot

• Dough seal (the traditional way): knead a soft dough from about 1 cup atta and water. Roll it into a long rope, press it all around the rim, and press the lid onto it. As it cooks, the dough hardens into an airtight seal. Break it open at the table for a little theatre.
• Foil and lid: cover the pot with a sheet of foil, crimp it tightly around the rim, then put the lid on top. Almost as good and much quicker.
• A heavy weight: if your lid is loose, put something heavy on it, like a stone mortar or a pan of water.
• A tea towel under the lid absorbs extra moisture and is good for plain pulao, but keep the cloth away from the flame.

The heat

Dum is about very low, even heat.

1. Start on high for 3–5 minutes, until you see or hear steam building at the edges.
2. Lower the heat to the lowest flame.
3. Put a tawa (flat griddle) under the pot. This spreads the heat and is the single best way to stop the bottom burning.
4. Leave it alone: 15–20 minutes for pulao and part-cooked rice biryani, 35–45 minutes for kachchi biryani with raw meat.
5. Rest 5–10 minutes off the heat before opening.

In an oven, dum is even easier: a sealed pot at 160°C for the same time gives very even heat from all sides.

Common problems

• Burnt bottom: the heat was too high or the pot too thin. Use a heavy pot, the tawa trick, and a little extra ghee at the bottom. A thin layer of potatoes or onions also protects the meat.
• Rice still hard: the rice went in too undercooked or the seal leaked. Sprinkle 3–4 tablespoons of hot water over the top, re-seal and give it 10 more minutes.
• Mushy rice: the rice was overcooked before layering, or there was too much liquid. Next time, boil it to 70–75% only (it should still have a firm core).
• No aroma: add saffron milk, kewra or ghee to the top layer just before sealing, not after.

Dum beyond rice

The same principle finishes Kashmiri dum aloo, dum qeema, and qormas cooked “on dum” for the final half hour. It’s also the idea behind dhungar, where a hot coal smokes the food inside a sealed pot.

Once you’ve mastered dum, try the recipes below, starting with a pulao and working up to a kachchi biryani.