Begin by preparing the bacon. Place the slices in a large skillet and cook over medium heat until crispy. Once finished, transfer the bacon to a plate lined with paper towels to drain any excess grease.

Next, remove most of the bacon grease from the skillet while retaining a small amount for flavor. Place the skillet back on medium heat and add the tomato slices. Sear each side for approximately 1 to 2 minutes, or until lightly browned and slightly softened. Remove them from the heat and set aside.

In a small bowl, stir the pressed garlic into the melted butter. Allow this mixture to sit briefly so the flavors can meld together.

Brush one side of each bread slice generously with the garlic butter. Stack the slices together, buttered sides facing inward, to make assembly easier. On the top slice of each pair, spread a thin layer of mayonnaise.

Evenly distribute the shredded cheddar cheese over the mayonnaise, followed by the seared tomatoes. Place the cooked bacon on top of the tomatoes and, if desired, sprinkle with additional cheese for extra richness.

Heat a clean skillet over medium-low heat. Carefully transfer the open sandwiches into the skillet, leaving the top slices off for now. Spread a thin layer of Dijon mustard on the unbuttered side of the remaining bread slices, then position them on top to complete the sandwiches.

Cook the sandwiches gently for about 4 minutes per side. Use a spatula to press down occasionally, ensuring even browning and helping the cheese melt thoroughly. Once the bread is golden brown and crisp, remove the sandwiches from the skillet.

Carefully lift the top slices slightly and tuck the romaine lettuce inside, placing it above the tomatoes and bacon. Close the sandwiches, slice if desired, and serve immediately.