Toast the coconut in a 12-inch heavy skillet over medium heat, stirring occasionally, until golden, about 3 minutes. Transfer to a small bowl and wipe out skillet. Place the skillet back over medium heat and add the oil. Once hot add the onion, garlic, ginger and serrano pepper, cook for 3-5 minutes or until the onions have softened. Add the zucchini, summer squash, spicy curry powder, garam masala and a good pinch of salt and pepper. Continue to cook the mixture another five minutes or until the vegetables and spices are fragrant. Now add the chickpeas, tomatoes and 1 cup water. Bring the mixture to a boil, reduce the heat and simmer for 10-15 minutes or until the sauce has thickened.
Meanwhile make the rava dosai (plural of dosa). In a four cup glass measuring cup or bowl combine the semolina flour, rice flour, white flour, serrano pepper, green onion, cumin seeds, salt and pepper. Add 2 cups water and whisk until combined. The batter should be thin, add more water if is seems too thick. Generously brush a 10-12-inch nonstick skillet with oil or butter and heat over medium-high heat until it shimmers. Stir the batter well and pour in a circular motion starting from the outside and going in, filling in the gaps as you continue to pour in a circle motion (don't worry if there are few tiny holes throughout the dosa). While cooking, drizzle butter or coconut oil onto the dosa. Cook, undisturbed, until dosa is set and edges are golden, about 2 minutes. Flip using a spatula (just like a pancake) and cook dosa until underside is golden in spots, about 1 minute more. Transfer to a plate. Repeat with the remaining batter, stacking and covering loosely with foil to keep warm.
Once the masala has thickened stir in the coconut milk and cook until combined. Remove from the heat and stir in the cilantro and toasted coconut.
To serve, spoon masala filling onto one half of the dosa. Pull the other half over top. Sprinkle with chopped cilantro. EAT!