1) Chop up the slices of prosciutto and a small onion. Then cook it with 2 tablespoons of oil until crispy.
2) Roll out the bread dough with a floured rolling pin to form a large rectangle. Spread on top the onion and prosciutto, 5 pitted and sliced black olives and a spoonful of chopped sage leaves. Then roll the dough on itself, starting from the longest side. Cut the roll into slices about 1 inch thick.
3) For a little extra flavor, brush the rolls with some melted butter, and bake for about 15 minutes.