Spiced Red Lentils with Caramelized Onions and Spinach

This slightly spicy dish uses a North Indian technique called tadka or chaunk: seasonings are fried in hot butter or ghee and then mixed with lentils just before serving to enhance the flavor.
Heat 2 tablespoons of oil over medium-high heat in a large nonstick skillet. Add the onion and a pinch of salt and cook, stirring occasionally, until lightly browned and very soft with crisp edges, about 30 minutes. Transfer half to a bowl and set aside.Meanwhile, put the lentils in a saucepan with 3 cups of water and bay leaves. Bring to a boil over medium heat, uncovered, and remove the foam. Simmer until tender, 5-10 minutes (they will fall apart a little). Remove the bay leaf and set the lentils aside - do not drain the water.Add the chili, ginger, coriander, turmeric and 1 tsp salt to the skillet with the onion and cook over medium heat until fragrant, about 1 minute. Add the spinach and cook, stirring occasionally, until completely wilted, about 3 minutes. Pour the onion-spinach mixture into the pan with the lentils and wipe the pan thoroughly.Heat 1 tablespoon of oil in a large skillet over medium-high heat. Add the cumin and garlic and cook, stirring, until the seeds sizzle, about 1 minute; stir in the lentils. Add some salt. Sprinkle the lentils with the remaining onion and serve over the rice.