A cross between meatloaf and meatballs, this sandwich promises to hold together without being messy.
Preheat the oven to 350 degrees F (175 degrees C).
In a medium bowl, mix together the ground beef, bread crumbs, onion, salt and pepper, garlic powder, and half of the mozzarella cheese. Form the mixture into a log, and place it into an 8x8 inch baking dish.
Bake for 50 minutes in the preheated oven, or until the center is no longer pink. Let stand for 5 minutes, then slice into 1/2 inch slices. Place a few slices onto each hoagie roll, cover with marinara sauce, and sprinkle remaining mozzarella cheese over.
Wrap each sandwich with aluminum foil, and return to the oven for 15 minutes, until bread is lightly toasted and cheese is melted. Let stand 15 minutes before eating. Each sandwich serves 2.
Per Serving: 491 calories; protein 29.3g; carbohydrates 43.1g; fat 21.4g; cholesterol 75mg; sodium 1068.5mg.