Make layers in the casserole dish with the hash browns. Put the sausage on top of the shredded potatoes. Add cheese and green chilis on top.
Prepare the egg mixture: In a big bowl, mix together the eggs, milk, onion powder, garlic powder, salt, and pepper. Mix thoroughly.
Add beaten eggs: Add the beaten eggs on top of the casserole.
Cook in the oven without covering for 35-40 minutes, or until the eggs are fully cooked.