Trim excess fat from the chicken breasts and pat them dry.
Place plastic wrap over the chicken and pound to an even thickness using a mallet.
Season both sides with salt, smoked paprika, and black pepper (or your preferred seasoning).
Heat your griddle to 375-400°F. Lay down the bacon and cook, flipping regularly, until halfway done.
Without adding extra oil, place the chicken directly in the rendered bacon grease.
Scrape excess bacon grease off the griddle, leaving enough to cook the onions.
Add sliced onions and cook for 3-4 minutes.
Sprinkle brown sugar over the onions and toss to coat. Cook until soft and caramelized.
Cook chicken for about 7 minutes per side, flipping once. Move the bacon to a wire rack when it finishes.
Use a meat thermometer to check for doneness of the chicken—internal temp should reach 165°F.
Top each cooked chicken breast with onions, bacon, and shredded cheese.