Preheat your oven to 350 degrees Fahrenheit.
Cut biscuits into quarters and spread them evenly in a greased 13x9 inch baking dish.
Cook bacon until crispy and crumble it. Brown Italian sausage in a pan until cooked through. Drain excess fat.
Sprinkle crumbled bacon and browned sausage over the biscuits. Sprinkle shredded cheddar cheese over the meat.
In a bowl, whisk together eggs, milk, salt, and pepper. Pour the egg mixture over the layered ingredients in the baking dish.
In a separate pan, melt butter (or bacon fat) over medium heat. Stir in flour to make a roux. Gradually whisk in half & half until smooth. Season with all-purpose seasoning, red pepper flakes, salt, and pepper. Simmer until the gravy thickens.
Pour the prepared gravy over the casserole.
Place the casserole in the preheated oven. Bake for 30-35 minutes until the top is golden and the eggs are set.
Let it cool slightly before serving. Cut into portions and enjoy your delicious Sausage Biscuits and Gravy Casserole!