Thaw hash browns by microwaving in microwave-safe bowl covered with paper towel at 20 second intervals, stirring in between. Once thawed, pat dry with a paper towel to remove any excess moisture.
Stir in melted butter. Spray down mini muffin tin liberally with nonstick spray. Fill each cavity with a tablespoon of hash browns and press to form crust.
Bake at 400 degrees for 10-15 minutes or until hash browns start to golden on edges. Remove from oven.
Whisk together eggs, bell peppers (diced), parmesan cheese, onion (diced), salt, and pepper.
Pour quiche on top of hash brown crusts. Lower oven temperature to 350 degrees and bake for 15-20 minutes or until lightly golden.