Instructions

• Cook the breakfast sausage in a skillet over medium heat until browned, then drain it well.
• Whisk the eggs, milk, salt, black pepper, and dry mustard together in a large bowl.
• Grease a 9-by-13-inch baking dish and spread the bread cubes evenly inside.
• Scatter the cooked sausage, cheddar cheese, red bell pepper, and green onions over the bread.
• Pour the egg mixture evenly over the casserole and press the bread gently so it absorbs the custard.
• Cover the dish and refrigerate for at least 8 hours or overnight.
• Remove the casserole from the refrigerator while the oven heats to 350°F.
• Bake uncovered until the center is set and the top is golden, about 40 to 45 minutes.
• Rest for 10 minutes before slicing and serving.