How to cook rajma properly, from dry beans

The soak is not optional

Dry kidney beans need eight hours in cold water, and they roughly double in size, so use three times the water you think. An overnight soak in the pot you will cook them in is the simplest version.

A quick soak works if you forgot: cover with water, boil hard for two minutes, take off the heat, cover and leave for an hour. It is not quite as good but it is close enough that the difference will not show once the masala is on.

• Eight hours cold, or one hour after a two-minute boil
• Three times the volume of water; they swell more than expected
• Discard the soaking water; it holds the compounds that cause the digestive trouble rajma is known for

Why they stay hard

Three things toughen beans and all three are avoidable. Salt added at the start slows softening, so salt them only once they have begun to give. Acid does the same but worse: never add tomato, tamarind or lemon until the beans are already soft, which is why every good rajma recipe cooks the beans separately from the masala.

Hard water is the third and the one nobody suspects. If your beans refuse to soften no matter what, cook them in filtered water with a quarter teaspoon of baking soda. Do not overdo the soda or they turn to mush and taste faintly soapy.

Old beans are the fourth cause and cannot be fixed. Dry beans more than a year old may never soften. If a pot has defeated you twice, buy a new packet before blaming yourself.

Timings that actually work

In a pressure cooker, soaked rajma needs five to six whistles on medium, then fifteen minutes of natural pressure release. Opening it early stops the cooking at exactly the wrong moment.

In an open pot, expect ninety minutes to two hours, topping up with hot water. Cold water added to boiling beans tightens the skins.

The test is not the clock. Take one bean out and crush it against the side of the pot with a spoon. It should collapse with no resistance at all. If the centre is still firm, none of them are done.

The step that thickens the gravy

Once the beans are soft and the masala is in, take a ladleful of beans, mash them properly against the side of the pot, and stir them back through. Then simmer for fifteen minutes uncovered.

That is the whole secret of a restaurant-thick rajma. It is not cream, it is not flour, it is bean starch released by physical force. Recipes that skip it produce beans floating in spiced water.

The other half is browning the onions properly at the start, which takes twelve minutes and cannot be hurried. Pale onions make a pale, thin curry no matter what you do afterwards.

Making it taste like the dhaba version

Three things separate home rajma from the version you remember eating out, and none of them is a secret ingredient.

The first is time. Restaurant rajma has usually sat for hours, and rajma genuinely improves overnight as the starch continues to thicken and the spices settle. Making it the day before is not a compromise, it is the better version.

The second is fat. Home cooks under-fat their gravies by roughly half. The oil that separates and floats on top is not a failure, it is the sign the masala is cooked, and skimming it off removes the thing you liked.

The third is finishing. A spoon of ghee, a pinch of garam masala and fresh coriander added off the heat, after the cooking is done, is a different layer from the spices cooked into the base. Restaurants do this to every plate. Home cooks do it to none.

Serving it as an actual meal

Rajma chawal is a complete meal and needs only rice, but three additions change it from food into a plate you look forward to.

Sliced raw onion with lemon and salt, made ten minutes ahead so it slackens. A spoon of thick curd, cold, straight from the fridge. And something crisp: papad, or a fried green chilli.

The contrast is the point. Rajma is soft, warm and rich, so everything you put next to it should be sharp, cold or crunchy.

If you are using tinned beans

Tinned kidney beans are fine and save two hours. Rinse them well, because the canning liquid tastes metallic and will carry through.

Skip straight to the masala, add the beans with half a cup of water, and simmer for fifteen minutes so they take on flavour. Mash a spoonful as above. The result is noticeably good, if slightly softer in texture than beans you cooked yourself.