Put the yeast and some of the flour in a small bowl. Stir in enough warm water to make a smooth paste. Cover and leave in a warm place to double in volume.
Boil, peel, and mash the potatoes. Melt the butter. Dice the prosciutto and provola.
Put the rest of the flour on your working surface. Make a well in the center and add some salt, the mashed potatoes, the melted butter, and the eggs.
As soon as the yeast mixture has doubled, pour it into the well, and knead everything into a smooth, elastic dough (about 10 minutes).
Knead the diced prosciutto and provola into the dough until everything is well mixed.
Butter a high-sided baking dish (about 7 in. diameter), put the dough in, and let it rise in a warm place until it has doubled in size. (We use a 9- or 10-in. deep-dish pie plate.)
Preheat the oven to 350 degrees, and bake the pizza for about 30-40 minutes.
We have served it at brunch as an accompaniment for daisy ham. We also enjoy it as the centerpiece of a supper with soup and salad. |