First I cut my bread in half (if not already cut) Put the oven on 350 & place the bread on a cookie sheet, place in oven for about 5mins. While that's in there toasting up a little bit I put the frozen meatballs in a ball to thaw out, (about 1min 30secs) once thawed I added the desired amount of spaghetti sauce I thought I wanted. That's about another 1min 30secs in the microwave. By the time your done with this your bread should be toasted so take that out the oven.
Put as many meatballs, as much sauce as you want. Put the cut up onions (if you want onions)on top of the meatballs. After that add the cheese! Lots of cheese. (: Once you made the sandwich place the sandwich back in the oven for about 3 to 5mins for the cheese & everything to melt & make sure everything is hot. Once out the oven sprinkle just a little bit of parmesan cheese. Then put whatever else you want on it! All done. So easy!