Preheat oven to 375°F Separate dough into breadsticks; cut each breadstick into 3 equal pieces. Working with one piece at a time, tuck ends under to meet at center, pressing to seal and form very small bun about Wz inches in diameter and Vz inch high.
Place buns seam side down on ungreased baking sheet. Bake 11 to 14 minutes or until golden brown. Remove to wire racks.
While buns are baking, prepare burgers. Gently mix ground beef and seasoning mix in large bowl. Shape beef mixture into 36 patties, using about 2 teaspoons beef per patty.
Heat large skillet over medium heat 30 seconds. Place half of patties in skillet; cook 4 minutes on one side or until browned. Turn and cook 3 minutes or until burgers are cooked through; top with slice of cheese, if desired. Repeat with remaining patties.
To assemble, split buns in half crosswise. Top bottom halves with burgers, pickle slices, small dollops of ketchup and tops of buns.