Place the bacon slices in a cold skillet, then turn the heat to medium. Cook until the bacon is crispy and browned, about 8-10 minutes, flipping occasionally.
Transfer the cooked bacon to a paper-towel-lined plate to drain excess fat. Keep the bacon warm.
While the bacon cooks, toast the bread slices until golden brown either in a toaster or in a separate pan over medium heat.
Lay one slice of toast on a plate, then place a slice of cheese on top to melt slightly from the residual heat.
Arrange 2 bacon slices over the cheese, then top with the second slice of toast, pressing gently to help everything stick together.
Place the assembled sandwich in a clean skillet over medium heat or use a panini press, and toast for 2-3 minutes until the bread is crispy and the cheese is melted inside.
Carefully flip the sandwich and toast the other side for another 2-3 minutes, until all sides are golden and the cheese is gooey.
Remove the sandwich from heat, slice in half if desired, and serve warm with a satisfying crunch and melty interior.
