Soak the rajma overnight or for 6 hours. Boil them till they are soft. Drain and discard the water. Slightly mash ½ of the boiled rajma and keep aside.
Heat a kadai and add oil. After oil is heated, add onion and fry till it turns pinkish.
Add garlic and saute, till garlic emits strong aroma.
Add chopped tomato and saute, till tomato turns mushy.
Now add the rajma and mix well.
Add the powders, namely turmeric powder, red chili powder, kitchen king masala and dry mango powder and mix well.
Add tomato sauce and mix.
Add salt to taste, mix and switch off the gas.