Ingredients

Makes five 9-inch-pizzas

　　5 packed teaspoons fresh compressed yeast* (from a 2-ounce cake)

　　1 tablespoon olive oil

　　a pinch sugar

　　1 cup cold water

　　21/2 to 31/2 cups all-purpose flour

　　1/4 cup white cornmeal

　　3 tablespoons whole-wheat flour

　　2 1/2 teaspoons salt

　　1/2 pound Portobello mushroom caps

　　1 3/4 pounds zucchini (about 3 medium)

　　1/2 cup chopped fresh chives

　　5 cups young fresh Robiola cheese (2,000 grams)

　　5 tablespoons cornmeal

　　5 tablespoons white truffle oil (a 1.8-ounce bottle)**

　　*available refrigerated at many supermarkets

　　**available at specialty foods shops

　　

Step 1

In a small bowl stir together yeast, oil, sugar, and about 3 tablespoons water until smooth. Stir in remaining water. In large bowl of a standing electric mixer fitted with dough hook whisk together 2 1/2 cups all-purpose flour, cornmeal, whole-wheat flour, and salt. With mixer on low speed stir in yeast mixture and blend until mixture forms a dough. With mixer on medium speed knead dough, adding enough of remaining 1 cup flour as necessary to prevent dough from sticking, until smooth and elastic, about 5 minutes.

　　

Step 2

Put dough in an oiled deep bowl and turn to coat with oil. Let dough rise, loosely covered with plastic wrap, in a warm place 1 hour, or until doubled in bulk, and punch down. Divide dough into 5 balls.

　　

Step 3

On a lightly floured surface roll out each ball of dough into a 9 1/2-inch round and stack, lightly floured, between sheets of parchment paper. Dough may be made 8 hours ahead and chilled, tightly wrapped in plastic wrap.

　　

Step 4

Preheat oven to 550° F

　　

Step 5

Cut mushrooms into 1/4-inch dice. Quarter zucchini lengthwise and cut off seed core. Cut zucchini into 1/4-inch dice and in a bowl toss together with mushrooms, chives, and salt and pepper to taste.

　　

Step 6

Spread 1 cup Robiola on each round of dough, leaving a 1/2-inch border around the edge. Sprinkle 1 tablespoon cornmeal on each of 2 baking sheets and transfer 1 pizza to each. Scatter about 2/3 cup mushroom mixture over each pizza and bake in batches in lower third of oven 10 to 12 minutes, or until crust is crisp and golden.

　　

Step 7

Transfer pizzas to plates and drizzle each with 1 tablespoon truffle oil. Top and bake remaining pizzas in same manner.