Add oil to a large pan on medium heat. Let the oil heat up for a minute or two. Add the cumin seeds and mustard seeds and sauté for one minute.
2 tablespoons oil, 1 teaspoon cumin seeds, 1 teaspoon black mustard seeds
Add the onions and sauté until onions are trasluscent and lightly golden brown.
1 medium onion
Add the dry spices, garlic and ginger and sauté for 30 seconds.
4 cloves garlic, ½ teaspoon turmeric powder, 1 teaspoon cumin powder, 1 teaspoon coriander powder, ½ teaspoon cayenne pepper, 1 tablespoon minced ginger
Add the tomatoes and cook until the tomatoes have broken down a bit. Maybe 5 minutes or so.
2 medium tomatoes
Add the yellow lentils, hing, vegetable broth and salt and stir. Cover and bring to a low simmer. Simmer for 20 minutes or until the lentils are soft and cooked. If the lentils are too thick, add in some more vegetable broth.
1½ cups yellow lentils, 4-5 cups vegetable broth, ½ teaspoon salt, ¼ teaspoon hing
Add in the lemon juice and top with fresh cilantro. Serve over basmati rice
juice from half a lemon