The bread commonly served in American (and probably Canadian) restaurants is known as Pullman bread. It’s baked in special pans that turn out nice, uniform loaves.
It isn’t just Americans who make soft, sweet white bread, which can actually be quite good:
And now let’s break for a joke:
“What’s the difference between your grandma and your granary?”
“One’s your born kin and one’s your corn bin!”
Heh, I crack myself up.
I laughed. 
The wrapper has a picture of Christ with microscopic words: “serving suggestion”.
I have, in the past, purchased holy water on Amazon.
Ba-dum-bump! * Tish! *
For a moment there, I thought you had passed water into the Amazon! 
Granary bread is wholemeal/wholegrain bread with malted grains in it. It’s definitely NOT the same as brown bread that is brown because of added molassess or malt extract.
If you can get a loaf that is made with wholemeal flour and contains whole seeds, that should be fairly close to the experience of eating granary bread - the seeds in granary are only malted barley and wheat, so a 23-seed (or whatever) bread that has pumpkin seeds and sunflower seeds will not be as close as a simpler multiseed loaf where you might be aware from the texture that there are whole seeds present, but perhaps could not immediately distinguish what they are - granary bread is delicious, but it’s sort of subtle too.
Oh, no. I’ve heard about those fish. 
A cheese and onion sandwich may actually not be much more than grated cheese and finely sliced shreds of onion between two slices of buttered bread. That’s how I make them sometimes - they are surprisingly good - it’s one of those things that is greater than the sum of its parts.
There is a slightly more refined version where the onion is very finely diced and mixed with the grated cheese plus some mayonnaise, and this is spread as the filling of the sandwich.
I have never in my life seen that shape bread served in a US restaurant. The only bread I have ever seen in that shape is Japanese milk bread, commonly served in Japan thickly sliced and toasted as part of breakfast. You can buy it in a few bakeries in the US.
If one is given a choice of breads in a US restaurant, either as breakfast toast or for a sandwich, the most common are white, whole wheat, and sourdough.
Cheddar cheese and onion sandwiches are common pub food in Great Britain. Others include cheese and pickle (mixed veg) and chicken and mushroom. All the ones I’ve had were made with baps (soft buns). But nothing beats grilled steak in a baguette with lots of English mustard.
I’ve had Pullman bread in a lot of US restaurants. Certainly ones that aren’t mom-and-pop establishments buying their bread from the supermarket.
Texas toast is made with pullman bread.
I assume most restaurants(steak joints) buy it from Restaurant suppliers already baked.
But it’s the same difference.
Ditto. I’ve only seen Pullman loaves in very specific uses, such as
A few things here:
- Good you mention the type of cheese, which no-one had up to that point. IMO a good mature cheddar or red leicester makes a bigger difference than type of bread. I think pretty much any bread will work, with the only bad option being a completely unflavored, texture-less white bread.
- Cheese and pickle is much more common IME than cheese and onion. And it seems that branston pickle can indeed be purchased in the US.
- I’ve never seen a chicken and mushroom sandwich, only pies. Is it a regional thing?
Actually, on the subject of chicken, coronation chicken could be a good british sandwich for the OP and others to consider trying.
Pubs had chicken and mushroom sandwiches in Cambridge. I didn’t see them anywhere else; but then again, I wasn’t looking for them. The chicken was similar to the kind in pot pies, i.e., boiled and then stripped off the bones. The mushrooms were sliced and probably cooked in the chicken broth.
I have a big jar of Branston Pickle in my cupboard, right next to my stock of Marmite. But I’m in Canada, not the US. I never looked for either when I lived there.
Thanks for that info.
Yeah, indeed the seeds are one thing that gives me pause because the seeds used could be wildly different on two otherwise similar loaves of bread. Some I can see, others should be on the ingredients label. Don’t want any “23-seed” bread as that would inevitably have far more seeds than i want.
I would love it if i could find a loaf which only seeds are malted barley and malted wheat as I think that would be close to “granary-style bread” but I don’t know where to get those.
In my searches I’ve found a couple that had malted barley but none with malted wheat.
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Yeah. Out here in the Bay Area it’s like that. But it seems in other parts of the US–especially east coast–it’s white, whole wheat, or rye. I like sourdough bread fine but I vastly prefer rye and it’s sometimes hard to get it out here (or at least have a decent variety to choose from) and rye is pretty expensive here (SF Bay Area) relative to the prices of sourdough and other breads.
Yeah, if you’re going to eat white bread, Texas toast is the best.
Ok, I know you said you’re not able to make the bread yourself, but it looks like one of the fastest, simplest loaves you can make. The linked-to recipe comports with my experience and memories of “granary style bread” served in England with many ploughman’s lunches I savored at pubs around the country:
You just stir the ingredients together, let time work its magic with the yeast. When you are ready for a loaf, you grab the chunk of dough you need, freestyle shape the loaf, let time work a little more magic, then slide it into the oven onto a stone and bake.
The website even gives you links to where you can purchase malted wheat flakes ($20 for 32 ounces, < choke! > but maybe they sell it in smaller quantities?) and malt powder, both from King Arthur. You can use the malt powder in bagel recipes, too.
Just a thought!