In a mixing bowl, place rava, rice flour, maida and mix well with water ( 2 cups approx). Keep aside for 3 hours covered.
After three hours, blend the batter in a mixer.
Add roughly crushed black pepper, cumin seeds, ginger, finely chopped green chilli, salt, asafoetida and mix well. You can add finely chopped onion to the batter and mix.
Adjust the water quantity, approximately 2 more cups.
Heat a dosa tawa and drizzle with oil. Hold the pan in you hands, slightly in slanting way. Pour a ladle full of batter in an arch. Then tilt to make it spread evenly everywhere. Fill any large gaps. Drizzle little more oil or ghee over.
Cook in medium flame until golden crisp. No need to flip.