Position rack in bottom of oven and place inverted baking sheet on top of rack; heat oven to 500 F.
On lightly floured surface, press pizza dough into 10-inch round circle and cover with towel while preparing toppings.
Sprinkle large baking sheet lightly with flour. Stretch pizza dough into oval, about 14-by-10 inches, and place on sheet. Drizzle with oil. Sprinkle with grapes, thyme and walnuts. Place baking sheet on top of sheet already in oven and bake until crust is bubbling and golden, 8-10 minutes.
Remove pizza from oven. Sprinkle with goat cheese and Parmesan. Season with pepper, to taste. Transfer pizza to board, cut into pieces and serve warm.
Notes
Nutritional analysis per serving: 350 calories; 10 g protein; 47 g carbohydrates; 14 g fat (36% calories from fat); 2.5 g saturated fat (6% calories from saturated fat); 5 mg cholesterol; 580 mg sodium; 1 g fiber.