846 W. 36th St., (410) 814-0652, luigisdeli.net
Start with half a loaf of crusty, fresh-baked Italian bread. Hollow out the middle. Add pitch-perfect marinara, authentic provolone, and two enormous homemade meatballs, halved, prepared with meat possessing the perfect lean-to-fat ratio. Top it off with grated Parmesan. Toast it. You have the most superb meatball sub imaginable. And it's so mammoth, you will be able to ration it into enough portions to last you for about a five meals.