The Perfect Breakfast Casserole | Cooking Professionally

Ingredients

• 1 large onion, finely chopped
• 1 tablespoon olive oil
• 2 cloves garlic, minced
• 1 (10-ounce) package frozen chopped spinach, thawed and squeezed dry
• 1/4 teaspoon salt
• 1/4 teaspoon ground black pepper
• 2 ounces pancetta or bacon, finely chopped
• 3 cups frozen shredded hash brown potatoes, thawed
• 8 large eggs
• 2 cups 2% milk
• 1 cup fontina cheese, shredded, divided
• 1 cup cheddar cheese, shredded, divided
• 1/4 cup fresh parsley, minced, plus more, whole leaves, to taste, for garnish
• 1 tablespoon Worcestershire sauce
• 1 teaspoon ground mustard
• 1/4 teaspoon ground nutmeg