Arrange the waffles in a single layer on a baking sheet. Bake at 425° 4 minutes per side, flipping them over at the halfway point, just until lightly toasted.
8 frozen Eggo waffles
Spray an 8x8" baking dish with nonstick spray and add 4 waffles to the bottom of the dish in a single layer, with minimal overlap.
Spread half the sausage evenly out overtop, then sprinkle half the cheese evenly out over the sausage. Repeat the layers.
1 lb ground sausage, 1 1/2 cups shredded cheddar cheese
Add the eggs, milk, salt and pepper to a mixing bowl then whisk them together until evenly combined. Pour the mixture into the baking dish as evenly as possible.
8 large eggs, 1 1/4 cups milk, salt & pepper
Cover the dish tightly with plastic wrap and chill in the refrigerator for at least 1 hour, or up to overnight.
Uncover the dish and bake at 325° for 50 minutes, just until the eggs are set.
Remove the dish from the oven and let it rest for 10 minutes.
Slice, serve warm, and enjoy!