Preheat the oven to 350 degrees. Line a shallow 2 ½ quart casserole dish with 2 of the flour tortillas.
Add ½ tablespoon olive oil to a deep saute pan. Heat over medium-high heat. Once hot, add breakfast sausage. Break apart and brown until just cooked. Remove from the pan, but leave the oil.
Add diced peppers, onions, and garlic. Cook over medium heat until softened, about 6 minutes.
While the peppers are cooking, thaw the hash browns in the microwave on the defrost setting. Add hash browns to softened peppers and onions. Cook for 5-10 minutes, until they are cooked through and hot, but not browned.
Remove peppers and hash browns from the pan. If enough oil remains, great. If not, add ½-1 more tablespoons of oil to grease the pan for the eggs. Whisk eggs, milk and pepper, salt, onion powder, and paprika. Add to the hot pan and scramble the eggs. Cook until JUST cooked through. Leave them with more moisture than not. Remove from the pan.
Layer sausage, hash browns and peppers, and eggs in the casserole dish. Add ½-¾ cup cheese. Top with remaining tortillas. Layer sausage, hash browns and peppers, and eggs once more. Top with remaining cheese and sliced green onions.
Bake, uncovered, for 35-40 minutes, until cheese is melted.