This gently spicy dish uses a North Indian technique called tadka or chaunk: seasonings are sizzled in hot oil or clarified butter, then swirled into the lentils right before serving for a massive flavor boost.
3 tablespoons vegetable oil, divided
1 1/2 large onions, halved and cut into thin half-moons
About 1 tsp. kosher salt
1 cup red lentils, rinsed well and drained
2 dried bay leaves
1/2 serrano chile, minced
1 tablespoon minced fresh ginger
1 teaspoon ground coriander
1/2 teaspoon turmeric
1 bunch (10 oz.) spinach (not baby), stems finely chopped and leaves cut in half; or use thawed frozen spinach
1/2 teaspoon cumin seeds
2 garlic cloves, minced
4 cups cooked brown basmati rice or couscous
How to Make It
Heat 2 tbsp. oil over medium heat in a large nonstick frying pan. Add onions and a pinch of salt and cook, stirring occasionally, until browned and very soft with crisp edges, about 30 minutes. Transfer half to a bowl and set aside.
Meanwhile, put lentils in a saucepan with 3 cups water and the bay leaves. Bring to a simmer over medium heat, uncovered, and skim foam. Simmer just until tender, 5 to 10 minutes (they'll fall apart a little). Remove bay leaves and set lentils aside--don't drain.
Stir chile, ginger, coriander, turmeric, and 1 tsp. salt into pan of onions and cook over medium heat until fragrant, about 1 minute. Add spinach and cook, stirring occasionally, until completely wilted, about 3 minutes. Stir onion-spinach mixture into pot of lentils and wipe frying pan clean.
Heat 1 tbsp. oil in pan over medium heat. Add cumin and garlic and cook, stirring, until seeds are sizzling, about 1 minute; stir into lentils. Season with salt. Top lentils with reserved onion and serve over rice.