Cut beans to small pieces. Boil them in water for 10 mins or until its cooked. Little water can be retained. Pressure cook the potatoes for 1 whistle. Peel the skin and cut into pieces.

Chop Onions, cut coconut and green chilies. Run coconut and green chilies in mixie to get a coarse paste. It shouldn't become paste but coconut should be like grated one.

Heat oil in a kadai, add mustard seeds and curry leaves. Then add onions, fry till they are brown in colour.

Then add coconut-green chilies paste. Fry till its well cooked. Then add the beans and potatoes with salt to taste. Cook on high flame to ensure the water in the beans gets evaporated. The result will be a well mixed veggie with all the spices.

Serve with Rotis if you cook with little water, else if you make it dry, serve with rice.