In a bowl add flour, salt and oil and mix well. Add water and knead into soft dough. You can also add ghee/clarified butter in place of water to knead the dough. Cover and let the dough rest for about 1 to 2 hours.
While the dough rests we will prepare the filling. In a wide pan, heat oil. Add cumin seeds to hot oil. Add finely chopped onions and green chilies and sauté until onions turn translucent.
Add ginger garlic paste and cook until the raw smell of the paste is gone.
Add all the spice powders and mix well. Add salt to taste and cook for about a minute on low flame. Turn off the flame and let the mixture cool down completely.
Lightly knead the dough and divide the dough and the filling into equal portions.
Heat oil in a wide pan for deep frying.
Roll one portion of the dough into smooth ball. Flatten it into 3 inch circle. Place a portion of the filling in the center. Bring all the edges to gather and seal it tightly. Roll this stuffed ball int0 3 inch circle. Keep aside.
Repeat this step for rest of the dough.
Deep fry small batches of kachori on medium flame for about 3 minutes. Reduce the flame and deep-fry on a slow flame for another 5 minutes. Remove from oil and drain it on kitchen paper.
Serve these delicious spicy masala onion stuffed kachoris immediately. Best accompaniment would be spicy green chutney and sweet dates-tamarind chutney.