In a mixing bowl, combine ragi flour, wheat flour, and cornmeal. Add a pinch of salt and enough water to knead into a smooth, soft dough.
Divide into small balls and roll out thin rotis about 3–4 inches in diameter.
Heat oil in a kadhai for deep frying.
Deep fry the rotis until they are half-cooked on both sides. Then, using tongs, fold each one into a taco shape while still in the oil and continue frying until golden and crisp. Place on paper towels to drain excess oil.
For the filling, heat 1 tbsp oil in a pan. Add chilli flakes and tomato paste (or ketchup), and sauté for a few seconds. Add chopped tomato, bell pepper, and paneer. Mix well and cook for 2–3 minutes. Then add mayonnaise, pasta seasoning, black pepper, and salt. Stir everything together until well combined.
To assemble, line each taco shell with iceberg, add any salsa (homemade preferably) of your choice and then add the veggie filling
Serve immediately for best crunch and flavor.