Wash the radicchio and slice, lengthwise. Reserve some radicchio for the garnish, and place the rest in a pot. Add the sparkling wine, a drop of oil, and a pinch of salt. Cover and cook over low heat for 5 minutes. On a work surface, lay you a slice of pancetta. Cover with the montasio and cooked radicchio. Roll up one at a time and place in a baking dish. Bake in 350°F oven for 5 minutes. Then plate the rolls and garnish with the raw radicchio.