Rinse the lentils under cold water until the water runs clear, then set aside.
Heat the oil in a saucepan over medium heat. Add the cumin seeds and toast until fragrant, about 30 seconds, releasing warm, nutty aromas.
Add the chopped onions to the pan and sauté until they turn golden and translucent, about 5-7 minutes, filling the kitchen with a sweet aroma.
Stir in the minced garlic and cook for another minute until fragrant and slightly softened.
Sprinkle the turmeric over the onion mixture and sauté briefly, about 30 seconds, to toast the spice and enhance its earthy scent.
Add the rinsed lentils to the pan, stirring to coat them in the fragrant spices and oil, then pour in the diced tomatoes and water or broth.
Bring the mixture to a gentle simmer, then reduce the heat to low. Cover the pan partially and cook for about 25-30 minutes, stirring occasionally, until the lentils are tender and have absorbed most of the liquid, creating a thick, velvety texture.
Uncover the pan, give the dal a good stir to ensure even consistency, and adjust the seasoning if needed.
Finish by stirring in chopped fresh herbs and a squeeze of lemon juice for brightness, if desired.
Serve the warm, thick dal in bowls, garnished with extra herbs if you like, and enjoy its comforting, earthy flavors.
