In a small bowl, combine the butter, grated Parmesan cheese, and garlic powder. Mix until well combined.

Take two slices of your chosen bread and spread the butter mixture on the outer sides of each slice.

Layer one slice with Havarti, Gruyere, sharp cheddar cheeses, and turkey cold cuts. Top with another slice of bread, buttered side out.

Heat a nonstick skillet over low heat. Place the assembled sandwich in the skillet and toast for 5-6 minutes until golden brown. Flip and toast the other side for another 5-6 minutes.

In a bowl, whisk together mayonnaise, red grape juice vinegar, grated Parmesan, garlic powder, Italian seasoning, and black pepper until smooth.

Chop lettuce, red onions, and banana peppers. Toss these vegetables with the creamy dressing.

After cooking, open the sandwich and fill it with the vegetable mixture. Slice in half and serve immediately.