In a large pot (6 to 8 quarts), cook bacon over medium-high heat, stirring often, until crisp, 3 to 5 minutes. Reduce heat to medium.
Add onion and garlic; season with salt and pepper. Cook, stirring occasionally, until onion is starting to brown, 3 to 5 minutes. Add mushrooms; cook, stirring often, until they are tender and pot is almost dry, 5 to 10 minutes (depending on type of mushrooms). Stir in tomato paste, and cook 1 minute more.
Add broth, barley, oregano, and 3 cups water; bring to a boil. Reduce heat; simmer, partially covered, until barley is tender, 10 to 15 minutes. Add more water to thin soup, as needed. Season with salt and pepper, and stir in vinegar. Ladle into bowls; sprinkle with parsley.
Oh man! My boyfriend and I loved this! 100%! I will be making it again and again. I used beef bouillon cubes instead of stock. So about two cups of water and 3 cubes then later added 3 more cups of water. I made this with the Onion Focaccia that was in this month's Everyday Foods.
Very disappointing. Won't be making it again.
This soup was OK, not great. Lacked flavor, tasted like something was missing. Followed directions to the letter. Needs lots of salt for any taste at all. If I made this again I would add some beef to it and maybe a little wine.
One of the people I served this to said "This is the best soup I have ever eaten."
I cut back on the vinegar to half what was called for. But it did brighten up the taste. It is so little vinegar as to be unidentifiable in the soup. Same thing with the tomato paste - there is not enough to be identifiable, but it seems to sharpen up all the other tastes.