Mix maida, rice flour and rava in a large bowl. Pour water little at a time and mix to make a thick, lump-free paste. Pour water to make a thin watery batter. Add cumin seeds, black peppercorns, curry leaves, chopped onions and green chillies and mix well.
Let batter rest for 1 hour.
Heat a tawa till hot. Stir the batter well every time before ladling out batter as the flours tend to sink to the bottom. Ladle about a ¼ cup of batter and pour on the tawa to make a rough circle. This batter doesn’t lend itself to spreading like regular dosai batter, so pour slowly in a rough circle filling out gaps. It doesn’t have to be perfect. Mine never are.
Drizzle a little oil all around the dosai. Cook till the underside is crisp and golden. Flip over and cook for half a minute.
Serve hot with coconut chutney.