M'm! M'm! Good!
Cooking while dieting presents many special challenges, but it also presents some opportunities. Since most of my cooking is limited to large batches of meals like low-fat, high-protein turkey chili, large batches of Greek-style yogurt, or highly flavored fresh pickles, when I cook something else, I really don't mind putting a lot of time into it. It may be possible to make onion soup without a large time investment (does Trader Joe's sell caramelized onions?), but I doubt it. Anyway, while the start-to-finish time is quite high, the effort is relatively modest, and much of the cooking requires only intermittent attention. It's a great thing to make on a weekend afternoon of chores and/or reading.
This soup succeeds or fails on properly (i.e., slowly) caramelizing the onions. Obviously, you can't burn them. If you undercook them, the soup will be good, but it won't have that wonderful flavor that you get from a good bowl of French onion soup. I was on vacation with the kids a couple of weeks ago, and we ate out one evening after a movie, and I encouraged L. to select French Onion as her soup choice. She turned up her nose at it, so I took it and had something of a spiritual soup. It might have been all that melted cheese and bread after so much fat and starch restriction, but I think it was just well-made soup. Because, while the cheese and bread were delicious, it was really the broth that made the soup, and it was the onions that made the broth.
Anyway, I set out to make a more diet-friendly version, and I think I succeeded very well indeed. The recipe below is as far as I can take the diet-friendly concept. The entire pot has, by my estimation, about 720 calories. I can easily get eight lunch servings from it, but as a dinner starter, you might want to divide it six ways instead. In any case, while I think the recipe below is yummy, you can abandon some or all of the diet features and perhaps take it even further. A second tablespoon of both butter and flour would not be amiss here. And using regular beef broth (from a box) instead of the fat-free, low sodium variety, does taste a little better, if all that sodium doesn't frighten you. I think, though, that the real change you might want to make is just to switch out the porcini and put in a larger quantity of shiitakes, which would add not very many calories at all. Also, if you double the amount of barley, you will have something much more like a stew than a soup, and it will be extremely good. I am tempted to add yet more barley sometime and call it a barley risotto, but right now I'm more interested in soup.
Even without these additions, though, you have something very hearty and warming. It would be even better, perhaps, in winter, but if you work and eat lunch in an air-conditioned office, like I do, it's very good now. It freezes and reheats perfectly, too.
You will have to forgive me for relying on boxed beef broth. I am sure that if you made beef stock from scratch, it would be even better, but I find the store-bought version relatively tasty, if sometimes overly salted. Also, I have a tough time laying my hands on the bones I'd need to make a good beef stock.
If you're not on a diet (or if you are but want to splurge), the perfect and obvious accompaniment would be slices of baguette topped with some Gruyere cheese, well toasted and then run under the broiler.
Onion Soup with Barley
1 very large (8-10 ounce) onion
1 T. butter
1 T. flour
1/2 cup dry red wine
2 quarts low-sodium beef broth
1/2 cup barley
1/4 ounce dried porcini mushrooms
Remove the root and outer skin of the onion. Quarter, then slice very fine.
Heat about a cup of the broth until it's steaming, then pour it over the dried mushrooms and let sit.
In a heavy pot, melt the butter. Add the onions, stir well to coat, cover, and cook over very low heat until the onions are thoroughly wilted, about ten minutes.
Remove the cover and cook very slowly until the onions caramelize. This will take somewhere between a very long time and an even longer time.
When the onions have browned nicely, add the flour and stir well. Cook over low heat for two or three minutes. Add the red wine and stir thoroughly, making sure all the bits are scraped off the bottom of the pan and incorporated into the liquid. Add the remaining stock, increase the heat to medium, and bring to a boil.
Add the barley, reduce the heat to a simmer, and cover.
Squeeze the mushrooms dry, chop them finely, and add them to the soup along with the broth they soaked in, leaving behind any grit.
Cook until the barley is tender, from forty minutes to an hour. Season as necessary with salt and pepper.