Heat oven to 350°F. Spray large cookie sheet with cooking spray. Unroll dough on cookie sheet; starting at center, press dough into 15x10-inch rectangle. Place cheese slices on dough to within 1 inch of edges. Top with pickle relish.
In 10-inch skillet, cook beef over medium-high heat, stirring frequently, until thoroughly cooked; drain. Add onion and seasoned salt; cook 2 minutes longer. Spoon mixture evenly over pickle relish on dough. Starting on 15-inch side, roll dough tightly. Pinch edges of dough to seal; turn ends under. Arrange dough diagonally on cookie sheet, seam side down.
Bake 30 to 35 minutes or until golden brown. Cool 5 minutes. Cut into 12 slices. Serve with ketchup and mustard.