Exactly! At least, if by brown mustard you mean coarse whole grain german mustard. And ideally the onion should be red onion rings… Mmmmm.
These were known as ‘heart burn deluxe’ sandwiches when I was growing up. Unfortunately, as I got older I learned the reason for the name. 
Not that I don’t still indulge now and then. 
These
Spread it on whole grain Wasa Bread and top with sweet pickles.
Yumm I think I’ll get some for lunch.
I haven’t had a liverwurst sandwich with mayo for years. But now temptation arises.
I might add onions. And breath mints.
You know, I was just reading an article about ‘tempering’ the flavor of raw onions by cooking them a tiny bit.
And now I’m wondering how a liverwurst sandwich with grilled onions will taste…
Braunschweiger on dark rye with onions and mustard was my dads’ favorite sandwich. When I was little I was told it was only for grown ups, which meant I really wanted to try it.
I like it. Lots. However, the high iron is not good for me, so I can only eat it infrequently.
We go to the local polish butcher 3x/year and I usually buy enough for two sandwiches, along with a loaf of fresh pumpernickel and some good milder cheese. Slap on some mayo, brown mustard, and a slice of sweet onion and I’m in heaven.
We always spread it on toasted rye bread. Rosen’s to be exact.
Probably like they belong together… most Braunschweiger or Liverwurst Recipes have raw, or often, cooked onions as a major spice/flavoring component.
I once had a liverwurst sandwich at a Deli that had so much liverwurst on it, that it made me sick from the richness. Must Have been a pound of gooseliversausage on there betwee the Rye, White Onion, and Yellow Deli Mustard (similar to Guldeman’s). I love the stuff, but it was kind of comparable to eating a stick of butter in richness.
Sorry, that’s Gulden’s… not “Guldeman’s”. However, it would be an excellent marketing coup d’etat to come up with a really great Premium Deli Mustard and market it as Guldeman’s. Seems like a no brainer, actually go back to the roots of the original Gulden’s as an award winning mustard with real flavor rather than the mass marketed dumbed down flavor that it has devolved into.
From that wiki… what is Warwickshire sauce? Antbody ever had it?
It’s Worcestershire sauce made without anchovies, for kosher diets. Or so the interwebs tell me.
Yes! When I was a kid, we had it in the fridge a lot. I loved it on white bread with Miracle Whip THIS thick and perhaps some Velveeta THIS thick! MMmmmm!
To me, there is only one way to eat it: sliced thick, very soft (preferably white, but ‘whole grain white’ will do) bread, a thin layer of mustard (must be plebeian yellow mustard for this purpose) on one of the slices of bread. This is a delicious sandwich, though I’ll grant you I have to be in the right mood for it.
My husband always grouses “Why don’t you just buy dog food? It’s cheaper!” to which I reply “Obviously you haven’t priced dog food lately”. 
I just tried it the cooked way. I sliced it, seared the slices in a bit of bacon fat until lightly browned, and ate it alongside some lingonberry preserves. It was great! The aroma is much like when you cook liver. My dog keeps running around the house searching for it.
I guess it’s time to seek out the good stuff at the German deli. At my supermarket, there’s no difference between liver sausage and braunschweiger. Time to explore.
You people are just plain sick.
White bread=NO.
Yellow mustard=NO
Mayonaise/Miracle Whip=NO
That’s for the $3.99/lb stuff, not your high-falutin’ $6.99/lb stuff.
Fair enuf. I got me some of my stuff three days ago. Almost too rich.
Now I have to get some of the goose stuff. I’ve seen it, I’ve heard about it, I’ve bought it for others. I’ve never eaten it. And I’ve got an open jar of ginger jam in the fridge.
I might never have the braunschweiger in a sandwich again, thanks to devilsknew. I just made the seared sliced braunschweiger with lingonberry preserves again - I think I’m in love. I used a bit of bacon fat, but butter, oil, or possibly dry would work, too. It’s lightly browned on the sides, and it gives it a nice, meaty flavor, and less liver-y. The preserves (from Ikea, but I’ve seen it around) aren’t too sweet, and the combination is sublime! I think whole-berry cranberry sauce might work just as well, unless the flavor is a bit too strong. The berry jam I tried a couple of days ago was okay, but it was a little too sweet to go well with it.
Today I’m really off to the German deli to see what wonders await me. That goose stuff might send me over the edge.
I tried something that didn’t quite work out - the Reubenschweiger: rye bread, braunschweiger, swiss cheese, thinly sliced red onion and thousand island, grilled. The thousand island didn’t really work, but I wonder what condiment might.
Next experiment: toasted rye, sauted braun and red onion, swiss cheese, ???
Maybe honey-mustard or poppyseed dressing. No sauerkraut? Actually, it sounds for the best.
Some balsamic vinegar? A little Major Grey’s Chutney?
My German deli has closed! The next closest German deli is 35 minutes away. Maybe the local gourmet grocery store has some of the fancy stuff in the deli case.