I have never eaten at a Maid-Rite but have eaten plenty of loosemeat sandwiches in NW Iowa and none of them had even a remote taste of dry soup mix or canned french onion soup.
I found this posted in a loosemeat forum from about 3 years ago and is similar to those I have eaten.
OK, here's the story from a recipe site.
The loosemeat was created in 1924 at Ye Old Tavern-now Gus' Family Restaurant on 14th and Jackson St. in Sioux City, Iowa. Nowadays you will find the original sandwich served at Bob's Drive Inn on Hwy 75, LeMars, Iowa just a mile or so out of Sioux City, at The Tastee Inn and Out, on Gordon Drive and at Miles Inn on Leech Ave. among others.
I learned to make Grandma Angie's version while cooking at her cafes/diners/taverns in Sioux City, Iowa when I came to spend summers with her from 1959-1968. Her version is the best (IMHO) and only deviates from the original recipe a tad. If you see a recipe for loosemeats that contains tomato juice-run! A loosemeat is a sloppy joe without the slop-so stay away from anything tomato-ey please!
These little sandwiches are great for football parties, slumber parties, with a cold beer on a sunny summer day, or just anytime you want a real taste of Americana cooking that takes just a few minutes with very little cleanup. These are typical Iowa tavern fare.
I loved these sandwiches so much when I was a kid that one day I ran into my Grandma Ang's tavern and asked for a "tavern" and they came served with one of those white thin sheets of paper under them-well I ate my sandwich half way gone before I realized I was eating the paper too:-) Enjoy!
1 lb of real good ground chuck or ground beef round or ground sirloin
1 tablespoon fat like lard or Crisco (if meat is round or sirloin)
2 teaspoons salt, just enough to lightly cover bottom of your skillet(this seems like a lot of salt but trust me on this)
1 onion, chopped fine
1 tablespoon prepared yellow mustard
1 tablespoon vinegar
1 tablespoon sugar
water, to cover
salt and pepper, to taste
1) Get out a cast iron skillet-they are the best for loosemeats-or other kind if you have no iron skillet.
2) Melt fat over medium heat and lightly salt bottom of skillet.
3) Break ground beef up in skillet and start crumbling it with the back of a wooden spoon-this is very important-the meat must end up being cooked up into small crumbles.
4) Add chopped onion while browning meat.
5) Keep working with the back of spoon to break up meat.
6) When meat is browned, drain off any fat and return meat to skillet.
7) Add mustard, vinegar, sugar, and just enough water to barely cover meat in the pan.
8) Cook, at a simmer, till water is all cooked out-between 15-20 minutes.
9) Adjust salt and pepper to taste.
10) Heat your hamburger buns-they're traditionally steamed for loosemeats-I like mine toasted lightly-do it the way you like it.
11) When buns are warm, put yellow mustard on them and add some dill pickle slices-I put on lots!
12) *If you start changing this recipe and using things like olive oil for the fat and dijon or honey mustard for the yellow mustard, you will not get the traditional yummy taste of a loosemeat sandwich.
13) Likewise, don't add any liquid smoke or worcestershire sauce.
14) Make them just like this the first time so you can sample the simplicity of this famous Midwestern treat.
15) If you want to start making changes after that by all means do so but I'd like you to taste the original recipe at least once.