How to Make Rava Dosa
To make rava dosa, start by mixing the ingredients for the batter. Next, heat up a skillet, brush the bottom with oil, and add the diced onions. Then, use a ladle to pour 1/2 cup of the batter in a circular motion into the hot pan. Sprinkle cilantro and 1 teaspoon of oil on top and cook each side for 1-2 minutes until golden brown. Finally, use a spatula to remove the dosa and repeat the process to use up the rest of your batter.
Combine the semolina and buttermilk. Whisk together the semolina and buttermilk in small mixing bowl until evenly combined. Cover the bowl and allow the mixture to rest in a warm place for 15 to 30 minutes. Unlike other types of dosas, rava dosa does not need to ferment for a long period of time. While this mixture rests, you can continue preparing the rest of the ingredients. Chop the onions and green chilli. Use a sharp kitchen knife to cut both ingredients into fine pieces. Remove the seeds and membranes from the green chilli if you would prefer a slightly milder flavor, or leave a few intact if you'd like something spicier. Note that the diced chilli will be mixed into the batter, but the diced onion will be spread into the batter separately. For this reason, keep the two ingredients separated after dicing them instead of mixing them together. Combine the remaining dry batter ingredients. Using a whisk or mixing spoon, mix together the rice flour, all-purpose flour, diced chilli, cumin seeds, salt, and ground black pepper in a separate large mixing bowl. Toss the ingredients together until they appear evenly distributed throughout the mixture. Add the semolina mixture to the bowl. Pour the semolina-buttermilk mixture into the dry ingredients. Stir until combined. Gradually add water. Add approximately 1-3/4 cups (440 ml) of water to the flour mixture, beating it well with the whisk. Continue until a thin, smooth batter forms. Add the water a little at a time, beating well after each addition. Working slowly can make it easier to incorporate the water more thoroughly. There should be no lumps left in the batter when it's ready, and the final consistency should be about as thin as buttermilk. Finished rava dosas are supposed to have a lacy appearance, and that appearance can only develop if the batter is thin. If the batter becomes too thin, however, you can sprinkle a small amount of rice flour into it to help thicken it to the proper consistency. You may also wish to check the taste of the batter after it comes together. Add more salt, if necessary, mixing well to distribute it throughout. Heat the skillet. Place a 10-inch (25-cm) non-stick skillet with shallow sides on the stove and set the burner to medium heat. For an even more accurate experience, use a tava-style griddle to cook the rava dosa. Any nonstick skillet should work well enough, though. Allow the pan to become very hot. Test the skillet by sprinkling it with a small amount of water. Once the water immediately sizzles and steams, the pan is hot enough. Note that the pan should remain on medium heat throughout the entire cooking process. If you set it to a higher heat, you'll likely burn the dosas. Brush oil over the surface. Dip a small piece of clean paper towel in cooking oil. Use it to wipe down the entire bottom of the hot pan, working carefully to avoid possible burns. Alternatively, you could drizzle roughly 1 tsp (5 ml) of oil into the pan and wipe it across the bottom with a large slice of onion. Sprinkle the onions on top. Evenly spread 1 to 2 Tbsp (15 to 30 ml) of diced onion over the hot surface. Don't add too many onions since doing so may make it more difficult to remove the dosa when it's done. Too many onions can also cause the dosas to tear when you attempt to flip or remove them. You'll need to work quickly after you add the onion to prevent the onion from burning before the batter cooks. Note that some people prefer to sprinkle the onion on top of the dosa batter instead of spreading it beneath. Both option are acceptable, and waiting until later may help prevent the onions from browning too quickly if you aren't confident about how fast you can work. Lightly mix the batter. Quickly mix the batter with your whisk immediately before pouring it onto the hot pan. You'll need to quickly mix the batter each time you plan to pour more of it onto the pan. Otherwise, some of the semolina may settle at the bottom of the bowl, and the final texture and taste of the dosas could be negatively affected. Pour the batter in a circular motion. Use a ladle to pour roughly 1/2 cup (125 ml) of batter into the hot pan. Pour the batter around the edges of the pan first, then wind your way inward toward the center. Only pour the batter in a single layer, and hold the ladle from a high of roughly 3 to 4 inches (7.6 to 10 cm) as you pour. Do not attempt to spread the batter. If there are large gaps within the batter, quickly fill in those gaps with more batter. Leave the small gaps alone, however. The final dosa should be lacy and filled with small pockets of air. Sprinkle with cilantro and additional oil. Quickly sprinkle the surface with some of the chopped cilantro. Pour another 1 tsp (5 ml) of cooking oil or ghee over the surface, as well. If you did not add the diced onion to the pan before pouring the batter in, you'll need to sprinkle it over the surface of the dosa batter during this step. Allow the bottom to brown. Cook the dosa over medium heat for at least 2 minutes, or until the bottom turns golden-brown. You should be able to see hints of golden-brown coloring peeking through the holes and edges of the dosa. The edges of the dosa should also begin to lift away from the pan. Carefully flip the dosa. Use a spatula to carefully flip the dosa over to the uncooked side. Drizzle this side with another 1 tsp (5 ml) of oil or ghee, as well. Since the dosa is so thin, it could rip and tear if you turn it too forcefully. Make sure that the bottom has finished cooking and flip it over as carefully as possible. If you're nervous about flipping the dosa, you could allow it to finish cooking without flipping it. The top will not brown as much if you do, however. Allow the second side to brown. Continue cooking the dosa for another 1 minute, or until the new bottom side turns a light golden color. This second side will be a little lighter than the first, but both sides should be golden and crispy. Remove the finished dosa from the pan. Using your spatula, carefully fold the dosa into a half-circle. Slide it out of the pan and onto a serving plate. Cook the remaining rava dosas. Cook the rest of the batter by following the same procedure. This recipe should be enough to prepare an approximate total of six dosas. You may need to lightly grease the pan with additional cooking oil in between dosas. Remember to quickly mix the batter before pouring any into the hot pan. If the batter becomes too thick as it sits, stir in another 1 to 2 Tbsp (15 to 30 ml) of water. Serve immediately. Enjoy the rava dosas while they're still hot. You can eat rava dosas on their own, but they're more commonly served with coconut chutney , sambar , or idli podi. 
Combine the semolina and buttermilk. Chop the onions and green chilli. Combine the remaining dry batter ingredients. Add the semolina mixture to the bowl. Gradually add water. Heat the skillet. Brush oil over the surface. Sprinkle the onions on top. Lightly mix the batter. Pour the batter in a circular motion. Sprinkle with cilantro and additional oil. Allow the bottom to brown. Carefully flip the dosa. Allow the second side to brown. Remove the finished dosa from the pan. Cook the remaining rava dosas. Serve immediately. 