Preheat oven to 375°F (190°C). Grease a 9×9-inch baking dish.
Toss diced sweet potatoes with olive oil, salt, pepper, and paprika. Spread evenly in baking dish.
Bake sweet potatoes for 15–20 minutes until slightly tender.
In a bowl, whisk eggs, milk, garlic powder, and a pinch of salt.
Sprinkle cheese, green onions, and cooked sausage or bacon over sweet potatoes.
Pour egg mixture evenly into the baking dish.
Bake for 20–25 minutes until eggs are set in the center.
Let rest 5 minutes before slicing and serving.