Dahl

• 4 tablespoons unsalted butter, divided
• 1 large or 2 small onions, finely chopped
• 2 cloves garlic, crushed
• A 2 inch piece of gingerroot, finely grated
• 2 tablespoons curry powder (use a good quality one from a brand you trust)
• ½ to 1 teaspoon cayenne pepper (optional)
• 3 cups water
• 1 400 mL (13.5 oz) can of full-fat coconut milk
• 2 tablespoons tomato paste
• 1 796 mL (28 oz) can of whole tomatoes (ideally unsalted)
• 1½ cups dried red lentils
• Juice of half a lemon
• 2 teaspoons garam masala
• Sea salt, to taste
• Fresh cilantro, yogurt, chili flakes and cooked basmati rice or quinoa for serving

Heat 2 tablespoons of the pot in a heavy-bottomed pot (I use my Le Creuset Dutch Oven) set over medium-high heat. Add the onions and cook until they are soft and starting to brown (5-7 minutes at least). Add the garlic and grated ginger and continue to cook, stirring regularly so the garlic doesn't burn, until the mixture is brown and very fragrant.
Stir in the curry powder and cayenne (if using) and let them cook for about 30 seconds. Be careful not to let the spices burn.
Add the water, coconut milk, tomato paste, and the tomatoes and their juices, crushing each tomato between your fingers as you add it to the pot. Stir in the lentils.
Bring the mixture to a boil, then reduce the heat to low and let it simmer until the lentils are very soft and most of the liquid has been absorbed. This will take about 30-40 minutes, but the time will depend on the lentils you use.
Stir in the remaining 2 tablespoons of butter (and more if you want to make this dahl a little richer), lemon juice, garam masala and salt (I usually add at least 1 teaspoon of sea salt).
Serve over rice or quinoa, garnished with yogurt, chili flakes and cilantro.
Leftovers will last for several days in the fridge or can be frozen for a few months at least. The flavour in this dish gets better with age.

Source