Mix nicely all-purpose flour, semolina, rice flour, salt, and red chili together in a bowl.
Now add chopped onion, curry leaves, green chilli, coriander leaves, grated ginger, and mix well.
Drizzle hot refined oil over the flour mixture and rub with your fingers to get a bread crumb like texture. Rub and mix the flour mixture using your fingers.
Using water 1/4 Cup at a time bind firm, soft, and smooth dough. Make sure not to use too much water dough should be like mathri/poori dough. Knead for 1 – 2 minutes.
Divide the dough into gooseberry size balls of equal size. Take one ball in between your palms and flatten gently with your fingers. Keep the thickness of vada similar to mathri.
Meanwhile, heat oil in a deep frying pan over medium heat. Once all the vada are shaped deep fry in oil in small batches. Fry till crisp and golden from both sides. Drain on an oil absorbent paper.
Serve Maddur Vada crisp and hot with coconut chutney.