01 - Combine lentils and water in a medium saucepan. Bring to a boil, then reduce heat and simmer uncovered for 20–25 minutes until tender. Drain excess water if necessary and set aside.
02 - Heat olive oil in a large skillet over medium heat. Add cumin seeds and toast for 30 seconds until fragrant.
03 - Add chopped onion to the skillet. Sauté for 4–5 minutes until soft and translucent.
04 - Stir in garlic and ginger. Cook for 1 minute until fragrant.
05 - Add diced tomato, turmeric, coriander, garam masala, chili powder, salt, and pepper. Cook for 3–4 minutes until tomatoes break down and spices are aromatic.
06 - Add cooked lentils to the skillet. Stir to combine and cook for 5 minutes, letting flavors meld. Add a splash of water if mixture is too thick.
07 - Reduce heat to low. Gradually add Greek yogurt while stirring constantly to create a creamy sauce. Heat gently for 2–3 minutes, ensuring yogurt does not curdle. Adjust seasoning as needed.
08 - Stir in spinach until wilted.
09 - Serve hot, garnished with chopped cilantro and lemon wedges.