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.