Soak beans for 30 mins in hot water or 1-2 hours in cold water. Discard water when you want to use.
In instant pot
In an instant pot, heat some oil. Add onions,Salt, ginger and green chillies.Sauté onions until light brown.
Add chopped tomatoes along with salt to it and cook until they soften.
Add turmeric powder, coriander powder along with red chilli powder. Mix well.
Add 2 cups soaked beans along with 4.5 cups fresh water and pressure cook in an instant pot for 10 mins at medium-high pressure mode. Release pressure after 15 mins.
In pressure cooker
Follow exactly the same steps as instant pot, just pressure cook it on low flame for 3-4 whistles.
You may garnish optionally with chopped coriander. Serve hot with rice or roti.
In a pot
Follow exactly the same steps as instant pot, just cook them in a covered pot until soft(around 30-35 minutes) ,adjust water accordingly. (I used 4 cups of water to cook with 1 cup of dried beans that were soaked for 2-3 hours)
You may use the canned beans as well. In that case, you can just make the onion tomato curry and add the can with water in a pot. No need to pressure cook. Let it boil for 10-15 minutes.Additionally, you may just use the store bought pasta sauce with canned beans if you need to skip the cooking process of the onion and tomato curry.You may skip the spices and just use curry powder with salt.