Mix all the ingredients (salt, oil, ajwain) except water. Add a little water at a time. Pat and knead well for several times into a soft pliable dough. Cover it with moist Muslin cloth and keep aside for 15 minutes.
For Stuffing :
In a bowl add mashed potatoes and all dry masalas (salt, chili powder, mango powder, garam masala) and green chilles, ginger and Mix well. Add green peas, cashews and raisins and mix well. Add coriander and keep aside.
To Proceed :
Make small rolls of dough and roll it into a 4"-5" diameter circle. Cut it into two parts like semi-circle. Now take one semi circle and fold it like a cone. Use water while doing so. Place a spoon of filling in the cone and seal the third side using a drop of water.
Heat oil in a kadhai and deep fry till golden brown (fry on a medium flame).
You can buy the best bay area samosas at the Passage to India Bakery. They come with tangy dipping sauce or yogurt with it as well. Popular Samosa Sauces