I have a cool cookbook called the Great American Meatloaf Cookoff, or
some such thing. Hundreds of variations.

I use only beef and the Bell's meatloaf mix. For spices, I like the
peppery Bell's stuffing spices, a half packet of Good Seasons Italian
dressing, worcestershire, loads of salt and pepper, onion, sometimes
finely chopped bell peppers, egg.

I don't use a loaf pan. Just form a loaf on a foiled baking sheet, with
bacon and A-1 on top.

Great hot with gravy, but the best is next-day meatloaf sandwiches*. I
tried microwaving it and re-baking it, but now I just throw a couple of
slices in a frying pan and heat them in their own fat. Mmmmmm, tasty.

*Why do so many foods, like American Chop Suey, taste better the next
day???