1Mix peach preserves and chipotle pepper. Let stand at room temperature at least 1 hour to allow flavors to blend.
2Butter 1 side of each of the bread slices. Spread preserves mixture on each of 4 bread slices with buttered side down. Layer each with 2 slices of cheese and arugula. Top with remaining bread slices with buttered side up.
3Place sandwiches in large skillet or griddle on medium-low heat. Cook 3 to 4 minutes per side or until bread is browned and cheese is melted. Cook in batches if necessary.