Split the rolls in half horizontally. On the bottom of each roll, spread 1-2 tablespoons of fig butter. Layer with a few slices of prosciutto, a small handful of arugula and about 3 slices of cheese. Top with the top slice of bread.
If using a panini press, heat and use as usual, cooking sandwiches until cheese is melted.
If not using a panini press, heat a griddle, grill pan or skillet over medium to medium-high heat (be careful not to get the pan too hot, or the bread will burn before the cheese has a chance to melt). Once hot, place the sandwich on the pan, then place a cast iron skillet or other heavy pan on top of the sandwich to press it down. Once the bottom of the sandwich is toasted and warm (probably 2-3 minutes), remove the skillet, flip the sandwich, and replace the skillet while the other side heats through.