- Preheat an electric panini maker on high heat according to the manufacturer's instructions.
- Place the bread slices on a cutting board. Brush one side of each slice with melted butter. Turn one slice over and sprinkle with the cheese. Top with the bacon and fried egg, and season with salt and pepper. Top with the arugula and the other bread slice, buttered side up.
- Place the sandwich on the preheated panini maker and cook according to the manufacturer's instructions until the bread is golden and the cheese is melted, 3 to 5 minutes.
- Transfer the sandwich to a cutting board and cut in half. Serve immediately. Serves 1.