Heat oven to 400°F. In skillet, cook bacon over medium heat, stirring occasionally, until crisp. Remove bacon; drain on paper towels. Reserve 3 tablespoons bacon drippings in small bowl; set aside. Discard remaining drippings; wipe skillet clean and set aside.
In 1-quart saucepan, mix 2 tablespoons of reserved drippings, the whipping cream, butter and cream cheese. Cook over medium-low heat, stirring frequently with wire whisk, until melted and blended. Stir in Parmesan cheese and 1 teaspoon of the garlic powder until well blended. Keep warm over low heat.
Spray 11x7-inch (2-quart) glass baking dish with cooking spray. Unroll dough in baking dish; press in bottom and up sides of dish. Bake 5 minutes. Meanwhile, in reserved skillet, add remaining 1 tablespoon bacon drippings, the zucchini, yellow squash, mushrooms, pepper and remaining 1/4 teaspoon garlic powder; toss to coat with drippings. Cook and stir over medium-high heat 3 to 5 minutes or until vegetables are crisp-tender. Stir in bacon.
Using slotted spoon, spoon zucchini mixture evenly onto partially baked crust. Pour sauce over vegetables. Top with tomato halves and mozzarella cheese.
Bake 16 to 20 minutes or until crust is evenly browned and cheese is melted. Let stand 10 minutes before serving.