Heat oven to 350°F. Separate dough into 5 biscuits. Spray large cookie sheet with cooking spray. Press or roll each biscuit into 5-inch round; place on cookie sheet. Melt 1 tablespoon of the butter; brush lightly on top of each biscuit. Sprinkle each with 1/4 teaspoon garlic bread sprinkle. Bake 5 to 7 minutes or until golden brown.
Meanwhile, melt remaining 2 tablespoons butter in 2-quart saucepan over medium-high heat. Add mushrooms and bell pepper; cook and stir 2 to 3 minutes or until bell pepper is crisp-tender. Stir in cooking sauce and chicken; heat to boiling. Reduce heat to low; simmer 5 minutes to blend flavors, stirring occasionally.
To serve, spoon chicken mixture into shallow serving bowls; top with Garlic-Butter Flatbreads.