Heat: Set the oven broiler to high, place a rack 6 inches from the heat.
Prep bread: Split the baguette or ciabatta, lightly butter the cut sides.
4 small ciabatta
Layer: Add tomato two thick tomato slices to one half of each sandwich, add 4 thin mozzarella slices on top (2.5 ounces each sandwich).
2 large tomatoes, 10 ounces fresh mozzarella
Broil: Place open faced on a sheet pan, broil 2 to 4 minutes, until cheese melts. Remove.
Sauce: Generously spread Pepperoncini Mayo on one half of the bread, 4 tablespoons each sandwich.
16 tablespoons Pepperoncini Mayo
Finish: Add a large handful of arugula. Optional: add more pepperoncini slices for pepperoncini lovers. Also consider warm rotisserie chicken for an extra hardy sandwich with added protein.
4 ounces Arugula, pepperoncini, rotisserie chicken
Close and serve: Close the sandwich, press gently, slice, enjoy.