Ingredients
For pizza dough
Preparation
Make pizza dough:
Step 1
In a large bowl stir together water and yeast and let stand until foamy, about 5 minutes. Stir in flour and salt and blend until mixture forms a dough, adding additional tablespoon water if too dry. On a lightly floured surface knead dough about 10 minutes, or until smooth and elastic. (Alternatively, dough may be made in a standing electric mixer. In bowl of mixer make dough as described above. With dough hook knead dough about 5 minutes, or until smooth and elastic.)
Step 2
Put dough in a very lightly oiled deep bowl, turning to coat, and let rise, covered loosely, in a warm place 1 1/2 hours, or until doubled in bulk. Punch down dough and divide into 4 equal pieces. Dough keeps, each piece put in a small, sealable plastic bag and sealed, pressing out excess air, chilled overnight or frozen 2 weeks. If dough is frozen, thaw overnight in refrigerator before using. Makes enough dough for four 12- by 6-inch oval pizzas.
Make the pizza:
Step 3
Preheat oven to 450°F.
Step 4
In a bowl toss squash with oil and salt and pepper to taste. Spread squash in one layer in a shallow baking pan and roast in middle of oven, stirring once halfway through roasting, 15 minutes, or until lightly browned. Remove pan from oven and loosen squash with a metal spatula. Squash may be roasted 1 day ahead and chilled, covered.
Step 5
In a medium heavy saucepan stir together milk and flour and bring to a simmer over moderate heat, stirring constantly. Simmer sauce, stirring, 2 minutes and stir in nutmeg and salt to taste. Sauce may be made 1 day ahead and chilled, covered.
Step 6
Increase temperature to 500°F.
Step 7
On a work surface sprinkled with 1 teaspoon cornmeal roll out 1 piece of dough into a 12- by 6-inch oval and transfer to a baking sheet. Repeat with remaining cornmeal and dough, ending up with 2 ovals on each of 2 baking sheets.
Step 8
Spread sauce on dough ovals, leaving a 1/2-inch border around edge of each pizza, and sprinkle with Parmesan, squash, chopped sage, garlic, and pepper.
Step 9
Bake pizzas in lower and middle thirds of oven 15 minutes, or until crusts are crisp and pale golden. Garnish pizzas with sage sprigs.
