Preheat your oven to 400 degrees F.
Place a piece of salami on top of each muffin tin cavity, then press down with a shot glass to form the cup shape.
Bake for 8 minutes, then remove them from the pan and finish cooling on a wire rack to drain off any excess grease.
In a medium mixing bowl, combine mayo, red wine vinegar, banana pepper juice, garlic powder, dried oregano, salt, and pepper. Whisk to form a creamy dressing.
Add finely chopped lettuce, diced tomatoes, chopped pepperoni, chopped banana peppers, and diced red onion. Toss the coat in the dressing.
Fill each salami cup with the salad mixture, then sprinkle shredded mozzarella cheese on top before serving!