Jacked Up Tuna Melt

8 slices bacon, cut in half crosswise
Two 5-ounce canned oil- or water-packed tuna, drained well
¾ cup mayonnaise
4 tablespoons panko bread crumbs
1/2 cup grated mozzarella
4 tablespoons minced red onion
2 tablespoons finely chopped pickled jalapeno peppers
Kosher salt and fresh-ground pepper, to taste
8 slices of your favorite, good quality bread
8 slices Pepper Jack cheese
2 medium avocados, halved, pitted, and flesh scooped
8 thin slices tomato
Adjust oven rack to middle position and preheat oven to 350°F. In a large cast iron or nonstick skillet, or using a griddle, cook bacon over medium heat, turning as needed, until well browned and crisp on both sides, about 7 minutes. Transfer bacon to paper towel-lined plate, and reserve bacon fat in a heatproof bowl; wipe out skillet.
Meanwhile, in a small mixing bowl, combine tuna, mayonnaise, panko, mozzarella, red onion, and pickled jalapeños. Stir, mashing very well with a fork or stiff rubber spatula, until well-combined and almost no flakes of tuna remain. Season with salt and pepper.
Using a pastry brush, lightly but evenly brush both sides of each slice of bread with reserved bacon fat. Using the same skillet or griddle, toast bread slices on first side over medium heat until nicely browned and crisp, about 3 minutes; using a cooking weight or spatula, gently press down on bread slices while toasting to ensure even heating and browning.
Flip bread and lay one slice of cheese on top of each bread slice. Mound avocado on 2 of the bread slices, spreading it in an even layer. Top avocado with tuna, spreading it in an even layer, followed by tomato slices and bacon. Close sandwiches, placing top bread slices cheese side down, and continue to cook until bottom of sandwich is well toasted; press down gently on sandwich with cooking weights or a spatula to ensure even heating and browning.
Flip sandwiches and cook until second side is well-toasted. Transfer tuna melts to a baking sheet and heat in oven until cheese is melted through, about 5 minutes. Serve.
