Preheat oven to 350F and spray an 13x9 baking dish with nonstick cooking spray. Set aside.
Mix the broth with the cheddar powder, black pepper, and parsley flakes in a large bowl until smooth before adding the Greek yogurt. Stir until smooth.
Add the onion, garlic, and hash browns to the yogurt mixture, stirring everything together until evenly coated.
Transfer the hash browns mixture to the baking dish, spreading it evenly across the dish.
Add the butter to a large bowl and microwave for 5-15 seconds until it's melted. Add the crushed Corn Flakes to the melted butter and gently fold the ingredients together until you have a crumbly mixture. Spread the mixture evenly on top of the hash browns.
Bake for 50-60 minutes or until the top is golden brown. Top with fresh chopped parsley, grated pecorino or parmesan cheese, and chili flakes, if desired.