Basic Indian Curry Sauce, also known as Bhuna Masala or onion tomato gravy, made with onions, tomatoes, ginger, garlic and spices. This is the base for many Indian dishes such as lentils and curries. This onion tomato masala is very versatile and freezes well. Perfect to have for those busy days when you want to make a curry in a hurry! freeze well for up to 6 months.