Pastry: Sift flour and salt into bowl. Stir in melted butter, then yogurt, then water. Stir together until blended. Dough will appear dry and lumpy. Roll dough on pastry board and cut into 2-3 inch circles.
Filling: In a large frying pan, melt butter over moderate heat. Add onion, apple and garlic and saute until just tender. Add the spices, salt, black and red peppers, and saute, stirring for 5 minutes. Stir in potatoes and peas. Adjust seasoning. Add yogurt. Chill.
Assembly: Place 1 tablespoon chilled filling on dough circle. Fold over to form a semicircle. Moisten edges with a little water and pinch to seal. Repeat rolling and filling.
Place 2 cups vegetable oil in large frying pan or wok and heat over high heat. Fry pastries 4 or 5 at a time, turning once, until they turn a deep golden brown. Drain on paper tow towels.
Serve hot. Makes 25 to 30 pastries.