4 cups Italian type 00 flour 2 medium potatoes ½ of one (¼ ounce) package dry yeast 1 pinch sugar ½ tablespoon salt 1 ¼ cup warm water 30 black olives (pitted) 1 tablespoon capers 4 ripe plum tomatoes 6 2/3 tablespoons extra virgin olive oil 4 medium onions sliced thin
Boil potatoes in salted water. Peel while still hot and mash in a bowl with a potato masher. Dissolve the yeast in some warm water and stir into the flour.
Add potatoes and knead until the dough is firm. Season with salt, a pinch of sugar and one tablespoon of oil. Cover with a towel and let it rest for at least a couple of hours in a warm room. Meanwhile, peel the onions and boil in a small amount of water for about 10 minutes. Drain well.
In a pan over low heat, sauté onions in 2 tablespoons of oil until translucent. Add capers and chopped tomatoes and cook for 10-15 minutes, stirring often. Season with salt to taste. Remove from the heat. Slice olives in rounds and add to the sauce. Divide the dough in half and roll it out into two rounds.
Press one into an oiled 12-inch baking dish. Pour the filling into this shell and cover with the second round of dough. Crimp along the top edge and prick with a fork. Brush the surface with some oil. Cook in a preheated 425°F oven for about 20 minutes.