Fan out apple slices and brie over one waffle. Drizzle with honey and sprinkle with black pepper. Place second waffle on top.
In a skillet over medium heat, melt 1/2 tablespoon butter. Cook sandwich until browned on one side, about 5 minutes. Lift sandwich up with a spatula, add remaining butter, then flip sandwich and brown on the second side, about 5 minutes.