Heat oil in a pan. Add cumin seeds and let them splutter for a few seconds.
Add chopped onion, garlic, and ginger. Saute until the onion starts turning brown.
Add red chili powder, turmeric powder, coriander powder, salt, and around a tablespoon of water. Mix and saute for about a minute on low flame.
Next, add tomatoes and green chili. Cook covered until the tomatoes turn mushy. Then cook uncovered for about 2-3 minutes.
Add tomato paste and saute for about a minute.
Add black-eyed peas. Mix and cook for 2 minutes before adding water.
Cover the pan and cook for around 5 minutes.
Add spinach and cook for another 5 minutes.
Finally add garam masala, lemon juice, and coriander leaves. Mix everything and switch off the gas. Serve hot with rice/ naan/ roti