Onion Tomato Thokku is a tangy and spicy South Indian condiment made with onions, tomatoes, and a blend of aromatic spices. It is a versatile dish that can be enjoyed with rice, roti, dosa, or even as a spread on bread. The slow-cooked onions and tomatoes create a rich and flavorful base, while the spices add a kick of heat. This thokku can be stored in an airtight container in the refrigerator for up to a week.