Preheat the oven to 350°F (175°C).
In a skillet over medium heat, brown the sausage, stirring until fully cooked. Drain any excess fat and set aside.
In a mixing bowl, whisk together the eggs, milk, salt, pepper, garlic powder, and onion powder until well combined.
In the 9x13 inch baking dish, layer the cubed bread evenly across the bottom.
Sprinkle the cooked sausage on top of the cubed bread, followed by the shredded cheddar cheese.
Pour the egg mixture evenly over the entire dish, ensuring all ingredients are coated.
Cover the dish with aluminum foil and bake in the preheated oven for 30 minutes.
After 30 minutes, remove the foil and continue to bake for an additional 15 minutes, or until the eggs are set and the top is golden brown.
Let the casserole cool for a few minutes before slicing into squares and serving.