How to cook dahl: a step-by-step guide

Everyone should have a good dahl recipe in their repertoire. Healthy and intolerance-friendly (vegan, gluten and dairy-free), it’s one of those dishes that is as great at a dinner party as it is at a packed lunch.

In current times of pandemic and pantry staples, dahl is your friend. Things like lentils, curry powders are mustard seeds are pantry essentials, and if we’re ever locked down, it’s comforting knowing that this comfort meal is not far away.

I’ve strived to replicate my grandmother’s dahl recipe for years. Eight years to be exact, going back to when I first blogged about it in 2012.  No matter what I did, it never quite tasted like hers. 

I’ve since realised that seasoned cooks have a way of explaining recipes. For instance, when cooking rice, both my grandmothers would stick their fingers into the rice pot and add water up to the first knuckle. It always worked, no matter if you were cooking one cup of rice or five. I don’t think I’ve ever really understood it.

Grandmothers explain recipes by taste, touch and feel. As an experienced cook, it makes sense to me now, but much harder to understand as a novice. Here, I’ve broken the humble dahl down into a step-by-step process for even the most uninitiated of cooks.

You can use almost any lentils to make dahl. Orange, red and yellow varieties are the most common. My favourites are red lentils (which look orange) and chana dahl, which are actually split brown chickpeas.

I think red lentils are the most forgiving, so I’d recommend starting with these. Chana dahl are larger, and have almost nutty flavour that I love.

Step 1: Cook the lentils with ginger and garlic

Soak lentils in water for 2-3 hours, until they’ve expanded in size. You don’t have to do this, but it does speed up the cooking time considerably.

Just like making a dahl soup, cook the lentils in water with some aromatics. The ratio of lentils to water will vary depending on the type of dahl used, but start with a ratio of 1 cup lentils to 3 parts water. You can add more water throughout the cooking process to adjust the consistency of your dahl. (I have always used a plastic rice cup to measure dahl, so it’s about 130g lentils to 500ml water for a four meal portion.)

Place the dahl in a pot with water, and add 3 cloves of garlic and 3 slices of ginger. Do not add salt at this stage, as it can make the lentils hard.

Bring to the boil and cook until the lentils are soft and have expanded, about 10-15 minutes.

If you’d like to freeze the dahl into smaller portions, this is a good stage to do it. Freeze the cooked dahl, and when you want to eat it again, add the vegetables and follow the steps below.

Step 2: Add vegetables (optional)

When the lentils are cooked, add the vegetables and cook for a further 5 minutes. Add more water if your dahl is getting too thick.

The reason that I’ve added the vegetables as a separate step is to factor in the different rates that the vegetables and lentils cook at. Depending on the lentils or the vegetables you use, the size you’ve cut the vegetables to – they will cook at different times. As you get more used to making this dahl with your favourite ingredients, you might be able to combine the first two steps.

You don’t have to add any vegetables at all if you’d prefer a simple dahl.

Use whatever you have lying around – I tend to use some combination of carrots, potatoes and cauliflower. Green beans, okra, eggplant or drumsticks (moringa) are all also good options.

Step 3: Add flavour – curry powders, etc

When the vegetables are cooked, it’s time to add flavour. This can be anything from curry powders, spices, chilli powder, turmeric or even a pinch of stock powder.

Tamarind water adds a welcome hint of sourness (a cut up tomato works too) and coconut milk adds creaminess. Mix and match depending on what you feel like, and depending on what you have in your pantry.  

It’s worth using a good quality curry powder from a specialty Indian/Sri Lankan grocer, not a generic supermarket variety. My favourites are Baba’s meat curry powder or sambar powder (Malaysian), or Ma’s unroasted curry powder (Sri Lankan). Any good quality specialty curry powder will do though – please don’t use Keen’s curry powder!

Keep in mind that if your curry powder isn’t fresh, you’ll need to add more than listed in this recipe to turn up the flavour.

Continue to add more water if you prefer a thinner dahl, bearing in mind that dahl will thicken up as it cools.

Step 4: Temper aromatics

Tempering is the most important step in making a great dahl. Even if you’d tipped everything into a pot up to this step, you’d be totally (ok, mostly) fine. Really.

Tempering or ‘tadka’ is a technique in which spices and aromatics are heated in oil or ghee to release essential oils from cells and enhance flavours. For some dishes, this can be done at the start of the cooking process, but for dahl, it’s done at the end.

Use a generous amount of oil and cook until ingredients are aromatic. For dahl, this includes sliced onions, black mustard seeds, whole or crushed dried chillies and fresh curry leaves (the magic ingredient)– dried curry leaves will just not have enough essential oils to flavour your dahl. In Sri Lankan versions of dahl, cut up pandan and lemongrass is also used.

Step 5: Season generously

Last but not least, season your dahl with salt.  Seasoning is a key step in any recipe, and dahl is no exception.

Being such a simple dish, dahl relies on salt to bring out its flavours. Season to taste – until you can just taste a hint of salt – as dahl is usually eaten with rice, the blandness of the rice will mute the saltiness.