Dissolve the yeast in the warm water for 5 minutes. Mix together flour and salt and stir in the yeast mixture with the oil. Knead and shape into a ball and allow to stand in a warm place until doubled in size, approximately 1 1/2 hours.
Sauté the onion until soft. Mix with the remaining ingredients.
Divide the pastry into 24 portions and roll out into 3 inch rounds.
Top each round with a spoonful of filling and enclose the filling to form a triangular pastry. Brush the pastries with oil and bake at 375°F for 15-20 minutes.
Serve with yogurt.