Saturday, June 5, 2010

Onion Soup

Wow, only a month and a day since my last post! There's been a lot of cooking going on, and I have some exciting stuff going on right now, but that'll have to wait for a later post. Hopefully, though, I will have more pics like this to share

So, the point of this post is to go over one of my absolute favorite dishes: the bistro classic French onion soup. The standard preparation is to caramelize onions in butter, then add beef stock and perhaps a little red wine and cook. Occasionally, in American recipes you'll find the soup thickened with flour, but the classic dish has a thin broth given body by the gelatin in the stock. (A well-made stock, using bones, is one of the most amazing things I know of to cook with, but that is a completely different post for another day.)

However, years ago, when my cooking skills were nascent at best, I read a brief mention in a Cook's Illustrated recipe of a French chef once preparing onion soup for the test kitchen where the only ingredients were onions, salt, pepper, and water. He spent hours building up a fond on the bottom of the pan, then deglazing with water, and repeating until the onions had softened to a dark color. The simplicity of the preparation really appeal to me, and I've made it a couple times. Let me tell you: the results are spectacular. The depth of flavor gives nothing away, but it is a time-consuming dish and requires - REQUIRES - a thick-bottomed pan: cast iron, copper, All-Clad. If you don't have a pan that strains the wrist when lifting it, don't even bother attempting this.

Because the key to this dish is low heat and patience.

Today, I experimented with a few things: pancetta, white wine deglaze, red wine deglaze, and tomato paste (aw yeah!). But I want to stress that what follows can be done using only water and onions, with some butter, and therefore can be an incredibly hearty and entirely vegetarian winter soup. Never mind that it's June 5th. With that, let's get on with it.

The first step, done last night, was to slice three pounds of onions. Then, I cut lardons from about a fifth of a pound of pancetta, rendered their fat, then removed them from the pot and added the onions. Below is a picture of the pancetta browning, with the onions in a bowl behind.

The onions were added, and softened over medium-low heat until a fond had formed. This takes a while, since the onions have to soften and their moisture cook out before the Maillard reaction can occur and develop that beautiful fond. Fond, in case you don't know, refers to the brown bits that form on the bottom of a pan. Le fond, in French, refers to stock, though, so don't act like you know anything now.

Once the first fond formed, I deglazed with six ounces of white wine. Deglazing just means pouring a liquid into the pan and boiling it to dissolve the fond in the liquid. At this point, I refilled the glass with six ounces of water, set it next to the pot, and waited until a fond formed again. I then added just enough water to deglaze the pot and a generous pinch of salt. In all, the six ounces of water allowed for eight deglazings. That took about two hours, but since my pan is a thick-bottomed cast iron masterpiece, it took very little attention from me. I'd check the pan about every five minutes and when the fond looked like the one below, I'd deglaze it.

Just before the final deglazing, I added about two teaspoons of roughly cracked black pepper and a bay leaf. Then, I deglazed with six ounces of red wine. This, as with the white wine before, is completely optional, although both wines do add a lot of flavor and some body.

I boiled off the alcohol, then added enough water to make it look like onion soup along with a tablespoon of tomato paste (aw yeah!), brought it to the simmer, and let it go for about half an hour.

The harsh flavor mellowed and came together beautifully and the broth gained body during the simmer, but my final tasting (or what I was hoping would be my final tasting) told me that the sweetness of the onions was way too strong and the salt had done as much as it was going to do. So, I squeezed a little lemon juice in to cut that sweetness, then let it simmer for five more minutes so the soup didn't taste like I'd just squeezed lemon juice into it.

Top it off with a broiled crouton with Gruyère on top and there it is: three-hour, four ingredient (five, six, seven, whatever, they're optional) onion soup.