In a large skillet, cook the beef, onion and pepper over medium heat until meat is no longer pink. Add garlic; cook 1 minute longer. Stir in flour,salt, pepper, mustard and ketchup; set aside.
Unroll dough starting at the seam. Pat into a 14 inch x 12 inch rectangle. Spoon meat mixture lengthwise down the center of the dough; top with cheese slices. Bring long sides of dough to the center over filling; pinch seams to seal.
Place seam side down on a baking sheet coated with cooking spray. Brush with the egg white. Sprinkle with parmesan cheese.
With a sharp knife, cut diagonal slits in the top of the loaf. Bake for 25 - 30 minutes or until golden brown.