Preheat the oven to 350°F (175°C).

Heat a non-stick skillet over medium heat and melt the butter.

Crack the eggs into the skillet and cook them sunny-side up or scrambled, depending on your preference. Season with salt and black pepper.

Place the bottom halves of the croissants on a baking sheet.

Layer each croissant with a slice of cheddar cheese, a cooked egg, and a slice of bacon.

Spread mayonnaise or honey mustard on the inside of the croissant tops, if desired, and place them on top of the assembled sandwiches.

Bake the sandwiches in the preheated oven for 5-7 minutes, or until the cheese is melted and the croissants are warm and slightly crispy.

Serve immediately and enjoy!