Preheat Panini* grill on high. Reduce heat to moderate and spray with cooking spray. Spread butter on 1 side of 8 bread slices and turn slices over. Spread inside of bread slices with mustard/mayo mixture.
TIP: Waffle maker, griddle or skillet may also be used.
Top 4 slices of bread with PERDUE® SHORT CUTS®, dividing equally. Place cheese over the chicken then top with remaining bread slices, buttered side out. Cook sandwiches until bread is golden and crisp, 4 to 6 minutes.
Cut into halves to serve.