Preheat the oven to 350 degrees F. Coat the inside of a 9-inch x 13-inch baking dish with non-stick cooking spray. Set aside.
Take the biscuits out of the tube and separate them. Cut each biscuit into quarters. Arrange them in a single layer in the baking dish. Set aside.
Cook the breakfast sauce in a large skillet over medium heat until cooked trhough. Drain any excess grease in the pan.
Add the cooked sausage over the biscuit pieces in the baking dish. Sprinkle half of the cheese over the sausage.
In a medium bowl, whisk together the eggs, milk, garlic powder, and pepper. Pour the egg mixture over the ingredients in the baking dish. Then sprinkle the remaining cheese over the eggs.
Prepare the country gravy in a medium saucepan according to the package directions. Pour the gravy evenly over the casserole.
Bake uncovered for 35 minutes. When ready the sides will be bubbling, the top will start to turn golden, and the eggs will be cooked.
Remove the casserole from the oven and let rest for 5-10 minutes. Cut into 8 slices and serve warm.