Peel the pumpkin and cut into 2-3" cubes; set aside. Heat oil in a large frying pan that has a lid. Fry the pumpkins on both sides fora couple of minutes until lightly browned.
Mix together ingredients for Sweet Tomato Sauce in a bowl then add to pumpkin mixture in fry pan. Cover and cook 20-25 minutes over low heat until the pumpkin is cooked and most of the liquid has evaporated. (I don't know how it's going to evaporate if the pan is covered -- -B.) Mix together the ingredients for the yogurt sauce.
Spread half the yogurt sauce on a plate and lay the pumpkin on top. Top with remaining yogurt and any cooking juices left over. Sprinkle with dry mint. May be served with chalow (basmati rice) and naan or pita bread.