3 cups red lentils (masoor dal)
1 medium yellow or red onion, roughly chopped
1 cup tomatoes, canned or fresh, finely chopped
1/2 teaspoon cayenne pepper
1 teaspoon ground cumin
1 teaspoon ground coriander
1/2 teaspoon ground turmeric
1 tablespoon sea salt
2 tablespoons vegetable oil
2 teaspoons cumin seeds
1 teaspoon black or yellow mustard seeds
1/2 medium red or yellow onion, finely chopped
15 to 20 fresh or frozen curry leaves (optional but worth seeking out)
1 14-oz can coconut milk