Tarka Dal with Spinach, for the Freezer

Why it works

The tarka is the technique worth learning. Whole spices bloomed in hot fat release fat-soluble compounds that never come out in water, which is why a dal finished this way tastes different from one where the spices went in at the start. It also means the flavour can be added fresh to a reheated portion, which is the single best trick for making frozen food taste cooked. Nutritionally this is a legume dish carrying 18 grams of protein and 13 of fiber a portion, and lentils have among the lowest glycemic responses of any carbohydrate staple. Turmeric goes in with fat and black pepper for the same absorption reasons that apply anywhere curcumin appears.

Ingredients

• 500 g red lentils, rinsed
• 1.5 litres water
• 2 tsp ground turmeric
• 1 tbsp grated ginger
• 4 garlic cloves, minced
• 400 g tin chopped tomatoes
• 250 g spinach, chopped
• For the tarka: 3 tbsp ghee or neutral oil, 2 tsp cumin seeds, 2 tsp black mustard seeds, 2 dried red chillies, 1 sliced onion
• Lemon and coriander to serve

Method

1. Put the lentils, water, turmeric, ginger, garlic, and tomatoes in the slow cooker and cook on low for four hours, or simmer on the hob for 35 minutes, until the lentils have collapsed.
2. Stir the spinach through at the end and let the residual heat wilt it.
3. For the tarka, heat the ghee in a small pan until shimmering, add the cumin and mustard seeds, and wait for the mustard seeds to pop.
4. Add the onion and chillies and fry until the onion is deep golden, then pour the whole thing over the dal and stir once, leaving some on the surface.
5. Freeze the dal without the tarka if you can, and make a fresh spoonful when you reheat. It takes two minutes and it is the difference between good and excellent.