Preheat your oven to 400°F (200°C) and prepare a 9x13 inch baking pan by greasing it with cooking spray or butter.

In a large sauté pan, add the Italian ground sausage over medium heat. Break it into crumbles and cook for about 5-7 minutes.

Open the canned Grand biscuits and cut each biscuit into eight equal pieces. Spread them in a single layer across the bottom of your prepared baking pan.

Evenly distribute the cooked sausage over the layer of biscuits in the pan. Then, sprinkle half a cup of both shredded cheddar and mozzarella cheese on top.

In a separate bowl, whisk together the large eggs, milk, salt, and black pepper until combined. Pour this mixture evenly over the layered biscuits and sausage.

Top the casserole with the remaining shredded cheddar and mozzarella cheese.

Bake for 25-35 minutes until the eggs are set and the top is golden brown.

Once baked, remove the casserole from the oven and let it sit for about 5 minutes before slicing and serving.