Preheat the oven to 450F and line a sheet pan with parchment paper or a silicone liner.
Place the thick slices of bread on the lined sheet pan, spacing evenly.
Spread 2-3 tbsp. of pizza sauce on each slice of bread. Top with ⅓ cup of shredded cheese, and top with 3 slices of pepperoni.
Repeat with the remaining 3 slices of bread.
Bake in the preheated oven for 10-12 minutes, or until the cheese is melted and the edges of the bread are crisp.
Cool for a few minutes, then slice and serve with your favorite side.