2 large onions, sliced into rings
a good slug of garlic paste
1 teaspoon of turmeric
2 teaspoons of cumin
2 teaspoons of garam masala
1 teaspoon of cinnamon
2 tablespoons of black onion seed (nigella, kalongi - all the same thing)
Start by sweating the onions slowly slowly in some butter for as long as it takes. They want to be completely brown and floppy but NOT BURNED. When that's done, add the garlic and allow it to cook for a few minutes before adding the spices and some water to make a thick paste. Allow this to cook for a few minutes more.
Then add the lentils. About 200g will make 2-3 big portions as a main course; you should barely cover the lentils with stock and then hover, stirring regularly, until they're soft. Add more water if it looks like it's going dry.