Parmesan-Ranch Pan Rolls

I recently found this recipe in an old Taste of Home magazine.  Warm rolls always seem to make dinner complete but who has time to make rolls from scratch all of the time.  Frozen bread dough takes the hassle out of making these rolls and no one will know you "cheated" unless you tell them.

18 frozen rolls, thawed
1 c grated Parmesan cheese
½ c butter melted
1 envelope buttermilk ranch salad dressing mix
1 small onion, finely chopped (optional)

In a small bowl, combine the cheese, butter, and ranch dressing mix.  Roll rolls in cheese mixture; arrange in two greased 9-in. square baking pans. Sprinkle with onion if desired.  Cover and let rise in a warm place until doubled, about 45 minutes.  Bake at 350° for 20-25 minutes or until golden brown. Remove from pans to wire racks.