Together Coarsely grind cumin seeds and black peppercorns. Combine rava, maida, rice flour, chopped green chillies, coriander leaves, curry leaves, required salt and water in a large bowl.
Then Mix everything well so that the batter should be slightly watery, Cover the bowl and rest batter for at least 2 to 3 hours.
After 3 hours the batter will be slightly thick because rava absorbs more water then again mix well the batter by adding little more water. When the tawa is smoking hot, heat a tawa or griddle,, take a ladle full of batter and start pouring the batter from the outside rim of tawa to inwards center of tawa. put 1 tsp oil around the dosa.
Large holes will appear on rava dosa, rava dosa with large holes and gap will be light and crispy. Cook the rava dosa on both sides on medium heat until golden brown and crispy. Serve hot rava dosa with Coconut Chutney or Varamilagai Chutney or Vengaya Sambar.