2) Slice the ciabatta bread in half. Toast the bread under the grill or in the sandwich toaster for about 2 to 4 minutes.
3) Spread the white truffle butter on the bottom layer of bread. Layer lettuce, sopressata, mozzarella, prosciutto, radicchio, sun-dried peppers and basil leaves on top. Drizzle on olive oil and balsamic vinegar and add salt and pepper to taste. Place the top on the sandwich and cut into 4 equal pieces.
4) Place the sandwich in the panini press or sandwich toaster and cook until the bread is toasted and the cheese is melted, about 5 minutes.