Position an oven rack in the center and preheat the oven to 350°F (175°C).
Line a 15×10-inch or larger rimmed metal baking pan with foil. Set an oven-safe wire rack over the pan.
Arrange the thick-cut bacon on the rack in one nonoverlapping layer.
Combine the brown sugar, crushed red-pepper flakes, black pepper, and optional cayenne in a small bowl.
Rub the spiced brown sugar evenly over the bacon, then drizzle the maple syrup over the coated strips.
Bake for 40–50 minutes. Begin checking at 40 minutes and remove the bacon when the coating is caramelized, the strips are browned, and the edges appear crisp.
Cool for 5–10 minutes so the coating can set. Transfer carefully using tongs or a thin metal spatula.