Cook bacon until crisp. Reserve 1 tablespoon of bacon fat.
Combine barbecue sauce and pulled pork.
Layer ingredients on one slice of sourdough. Begin with 2 slices of white cheddar,1/2 cup pulled pork, 2 slices of gouda,1/2 cup of grilled onions, a few slices green apple, 4 slices of bacon, 2 more slices of white cheddar and top with another slice of sourdough. Repeat with remaining ingredients.
Heat reserved bacon fat in a large skillet on medium-high heat. Carefully place sandwiches in skillet and toast until bread is golden brown and cheese melts, about 3-4 minutes. Flip sandwiches and repeat. Remove from skillet and enjoy!