After dissolving the yeast in warm water, add flour and salt, knead a soft dough and leave it for 1 hour. Finely mince all the vegetables and put them in a large bowl. Add the meat, spices and tomato paste and mix all the ingredients well. Divide the dough into 4 equal parts and thin it with a rolling pin to form a long pita. Spread the inner stuffing on the dough you opened and fold the edges so that they are not too wide. Bake the pitas you placed on the oiled tray in a 230 degree oven for 15 minutes and serve.