Here’s a sandwich I came up with years ago at the firehouse. The guys always loved them.
Split and spread onion hamburger buns with garlic butter, sprinkle some parmesan or romano then grill or broil. Split lengthwise and grill or pan fry some 6" or so red hot polish type sausages. Dump a generous serving spoon worth of heated marinara sauce over the sausage pieces on each bun half, then plop on some shredded mozzarella and shredded hard cheese and a little handful of sliced spring onion. Close it up and serve.