Preheat oven to 350 degrees. Spray a 12 count muffin tin with non-stick cooking spray.
Heat butter or oil in a medium skillet. Add breakfast sausage and veggies. Cook until sausage is no longer pink and vegetables are tender.
Place 2 TBS of sausage & veggie mix into each prepared muffin cup. Sprinkle 1 TBS of cheese over sausage and veggies in each muffin cup.
Crack 10 large eggs into a large bowl. Add milk, paprika, garlic powder, onion powder, salt & pepper. Whisk until well combined. Pour egg mixture into each muffin cup about 3/4 of the way full. (Do not over fill.) Top with green onion slices.
Place muffin tin onto a large sheet pan (this will prevent any spillage into oven) . Place into preheated oven and bake for 15-20 minutes until eggs are set. Insert a toothpick into center of egg muffin to test for doneness. If it comes out clean, pull them out of oven or leave them in a few minutes longer.
Remove egg muffins from muffin tin right away so they don't stick. Serve and enjoy.