Keerai vadai is a popular South Indian snack made with lentils and spinach. It is a crispy and flavorful fritter that is perfect as an appetizer or tea-time snack. The vadai is made by grinding soaked lentils with spinach and spices, and then deep-frying them until golden brown. The addition of spinach not only adds a vibrant green color but also enhances the nutritional value of the vadai. Serve these delicious vadai with coconut chutney or sambar for a complete meal.