1.Mix flour, egg, baking powder, sugar, salt, yogurt, milk, and oil until combined. Gradually add 1/3 cup water, and knead dough until firm but not too soft. Let dough rest in a bowl covered with damp cloth for at least 2 hours.

2.Place pizza stone in oven, and heat to 350 degrees. Divide dough into four pieces, and knead each piece on a floured surface until smooth, forming into a ball. Let rest 10 minutes.

3.On a lightly floured surface, press each ball into a disc, eight inches in circumference. Cover entire surface with onions, peppers, and coriander. Place on pizza stone in oven, and bake until bread puffs up and brown blisters form on the surface, 5 to 10 minutes. Remove from oven, and brush w/melted butter.