Heat the oil in a large pot over medium heat. Add cumin seeds and sauté until fragrant.

Add chopped onion, garlic, and ginger. Cook until the onion is translucent.

Stir in the chopped tomato and cook for another 2-3 minutes.

Add the rinsed lentils, turmeric, coriander powder, and salt. Stir to combine.

Pour in the vegetable broth and bring to a boil. Reduce heat and simmer for 25-30 minutes, or until lentils are tender.

Stir in the spinach and garam masala. Cook for an additional 5 minutes.

Serve hot with rice or naan.