1/2 cup warm water (between 100 and 110 degrees, so you don't kill or chill the yeast)
1 tsp. active dry yeast
1/2 tsp. salt
2 tbsp. olive oil
1 to 2 cups all-purpose or whole wheat flour
1 (8-oz.) can whole tomatoes
Sea salt and pepper, to taste
1 clove garlic, crushed
3/4 cup shredded fontina cheese
2 cups loosely packed baby arugula
2 oz. thinly sliced prosciutto, torn into strips
Extra virgin olive oil, for drizzling
Coarsely ground black pepper, to taste
Black olives, sliced
Button mushrooms, sliced
Italian sausage, cooked and crumbled
Bell peppers, diced or sliced
For dough: Measure water into a large bowl. Add yeast and stir. Add sugar, salt and oil and stir well. Add 1 cup of the flour in small amounts and stir well after each addition. Continue adding just enough flour so dough is not sticking in clumps to your hands or bowl. Using your hands, knead dough for 2 to 3 minutes on a lightly floured surface. Divide dough into pieces and work into balls. Place balls in a large, lightly oiled casserole dish and cover with plastic wrap and chill. Before using dough, allow to sit out at room temperature for 1 hour.
For pizza sauce: Strain tomatoes and remove half the liquid and reserve. Grind tomatoes through a food mill using the #2 plate, adding reserved liquid as needed. No food mill? Use a blender or food processor—just a few pulses will do. Season with salt and pepper. Set aside.
Preheat oven to 475 degrees. Lightly sprinkle rimmed baking sheet with flour. Roll out pizza dough on lightly floured surface 1/4-inch thick. Using 2 1/2-inch diameter cookie cutters, cut 16 dough rounds.
Arrange rounds on a parchment-lined baking sheet. Brush all over each dough round with crushed garlic. Sprinkle rounds with fontina cheese, dividing equally.
Bake pizzettes until golden brown, about 12 minutes. Remove from oven, then scatter arugula over pizza and drape prosciutto over arugula. Drizzle with olive oil and season with pepper. Serve immediately.