A sandwich with arugula, jambon, and Emmental cheese
Cut the ciabatta bread in half
Slice slab bacon into 1cm thick pieces
Pan-fry the bacon until golden brown
Thinly slice the onion
Cut the tomato into rounds
Spread butter on the inside of the ciabatta bread
Layer the grilled bacon, onion, and tomato in order on the bread
Drizzle ketchup or mustard sauce
Top with the other half of the bread to finish the sandwich