Preheat oven to 350° and spray a 13 x 9 baking dish with a non stick spray. Set aside.
In a frying pan, cook ground beef, onions, garlic, salt, pepper and crushed red peppers until meat is cook thoroughly and onions are translucent. Drain and return to pan.
Place frozen hash browns on countertop to defrost.
In a large mixing bowl, mix all ingredients together except the ground beef and hash browns until combined (set aside 1 cup of grated cheese which will be used for topping).
Once combined, stir ground beef and hash browns into mixture.
Spoon into prepared baking dish and top with remaining cheese.
Place croutons into a large baggie, crush, then add melted butter, seal bag and mix together.
Place crouton mixture on top of cheese. Cover with foil, bake for 40 minutes.
Remove foil, continue baking for an additional 30-35 minutes, until topping is lightly browned, cheese is bubbly and hash browns are heated thoroughly.
Recipe adapted from my Cheesy Sausage Hash Brown Casserole.