Combine the flours, yeast, salt and water in a mixing bowl. Mix and knead to form a smooth, soft dough. Transfer to a lightly greased bowl, cover and set aside for 2 hours.
Divide the dough into 6~8 equal size pieces. Form each piece into a ball, cover and set aside for 20 minutes.
Preheat the oven to 425°F. Place a baking stone in the oven to preheat.
Roll each ball into a 5~6" round dish. Press the fist into the center of the dough to form a indentation. Traditionally this is then pierced with a stamp but a fork would do the job as well. Brush the top of the bread with milk or oil and sprinkle with nigella or sesame seeds.
Place the bread on the baking stone and bake for 15 minutes or until the crust is nicely browned. Serve right away.