01 - Preheat the oven to 375°F (190°C). Lightly grease a standard 6-cup muffin tin.
02 - In a small bowl, blend softened butter with minced garlic and chopped parsley until well combined.
03 - Flatten each bread slice with a rolling pin. Trim crusts as needed to ensure a good fit in the muffin cups.
04 - Spread one side of each bread slice with a thin layer of garlic butter. Press the slices, buttered side up, into each muffin cup to form a nest shape.
05 - Sprinkle a small amount of grated Parmesan cheese into the bottom of each prepared bread cup.
06 - Crack one large egg into each bread cup. Lightly season each egg with salt and ground black pepper. Add shredded cheese on top if desired.
07 - Transfer muffin tin to the oven. Bake for 16 to 18 minutes, or until egg whites are set and yolks are cooked to the preferred consistency.
08 - Let the egg cups cool for 2 minutes. Carefully loosen edges and lift out using a small spatula.
09 - Serve warm, garnished with additional chopped parsley if desired.