I like contrast. It looks good when there is contrast in a painting. I think it's also nice to have contrasts in flavors. Perhaps that's why I find the creaminess of a mild, hearty soup is paired well with the tang of sourdough. So, what is sourdough, and why is it so good with soup?
Sourdough originated in ancient Egypt, and is made when dough is fermented for a long time using naturally occurring yeasts and lactobacilli. The presence of the lactobacilli produces lactic acid, thus generating the slightly sour taste in the dough. Other breads are made with cultivated yeast, and it is a quicker process.
Okay, don't get squeamish. Knowing the truth about "what is sourdough" shouldn't ruin your appetite. The whole bacteria thing is truly nothing to be concerned with. It's all natural, doesn't make you ill, and yields a flavor that is much beloved.
That brings us back to the contrast thing. Imagine a simple, creamy soup enhanced with the pizazz, but not overpowering taste, of sourdough. Nice, right? Not every soup is going to go well with sourdough (think Chinese hot and sour) just as every wine does not pair well with blue cheese. But there are recipes abounding that put the two together, and I like it.
Here's a recipe for mixed onion soup served in a sourdough bread bowl. You may have seen the likes of this in various restaurants. Certainly a sensation to warm you as the temperatures begin to drop with the leaves.
There is even evidence of a restaurant in a town known for it's sourdough, San Francisco, that offered a unique sourdough enhanced soup. Old Krakow once offered a white borscht with potatoes, carrots, onions, and kielbasa that was thickened with.... wait for it... naturally fermented flour (sourdough).
Another recipe I found calls for sourdough accompaniment. It's a cauliflower soup with garlic cheese dippers. The dippers are made with, you guessed it, sourdough. I also like the simplicity of a tomato soup, or onion soup, with sourdough croutons.
If you are like many people, and find soup making time consuming enough, you can always substitute those croutons or dippers with a ready-made sourdough side, like John Wm. Macy's CheeseSticks. They are made with twice-baked sourdough, and come in various flavors.
Hankering to make your own sourdough bread, with or without soup? Try this recipe from allrecipes.com
So as fall settles in, then slowly turns to winter, and your cravings turn to warm comfort food, don't forget the contrast. No need to ask "what is sourdough, and why is it so good with soup?" Just trust me, and give it a try. See how a sour tang can truly be a sweet addition to a warm bowl.