Cook sausage patties in a skillet until cooked through. Remove from pan and place on a paper towel to allow for the grease to drain.
Heat a clean skillet over medium heat.
Assemble sandwich by smearing a little bit of pesto on one slice of bread. Follow with a slice of provolone, a sausage patty and then a slice of mozzarella.
Add a tablespoon of butter to the skillet. Place the sandwich in the skillet and cook until the bread has turned golden brown. Flip sandwich and cook until cheese is melted and bread is golden brown on the other side.
Repeat steps 3 and 4 to make remaining sandwiches.
NOTE: Sandwiches can be served with a side of marinara sauce or tomato soup for dipping!