Soupe à l'Oignon Gratinée: When it Becomes Impossible to Discern Either Cheese or Onion

"The soup is ready when the surface looks like a crusty, golden cake and the inside is unctuous and so well blended that it is impossible to discern either cheese or onion..." (From ''Gastronomie Pratique,'' by Ali-Bab, 1907)

As a rule, I try to focus primarily on my own recipes; it helps me to be more adventurous and thoughtful in my cooking. But quite frankly, the soup - or rather soupe - I made on Sunday was so absolutely perfect that it would be a selfish, selfish thing for me not to share the recipe for Soupe à l'Oignon Gratinée with the world.

At some tragic point in every bowl of French Onion Soup, the diner realizes that she has somehow managed to eat all the "good stuff" and is left with only a lonely bowl of buttery broth.* While indeed the broth that is left is as pristine in form as any broth could aspire to be, the very memory of crusty bread, melting onions and salty cheese is enough to make the diner shed tears of remorse into her broth, making it far too salty to finish.

The magic of this Soupe à l'Oignon Gratinée is that by the time you're done caramelizing, simmering, baking and browning, the broth has transformed itself into a perfect, silky, mushy bready delight. Really, it's the very best part of French Onion Soup, without the morose slosh of unwanted broth.

Grossly, Guy kept exclaiming, "I wish I could take a bath in this!" While all guests were duly repulsed, by the end of the meal we were willing to concede that he may be onto something.

Soupe à l'Oignon Gratinée

Originally published in Ali Bab's Gastronomie Pratique; republished in the New York Times in 1974, and then again this past February. The method carries my reflection on the process.

Ingredients
1 baguette, cut into 30 1/2 inch slices
9 tbs. butter, softened
9 oz gruyere, grated (the original calls for emmantal, but I'm a sucker for gruyere); 1/2 cup reserved
8 medium yellow onions, thinly sliced (about 12 cups)
1 tbs kosher slat, plus more to taste
1 cup tomato puree (I used canned diced tomatoes)

Method
Prepare the ingredients: Preheat the oven to 350 degrees. Arrange baguette slices on one or two baking sheets and toast for about 10 minutes. Flip and continue toasting for 10 minutes more. Remove from oven to cool.

While the toasts cool, prepare the onions: melt 4 tbs. butter in a very large saucepan (because have you stopped to think about the sheer volume of 12 cups of sliced onions?). Add the onions, season generously with salt and saute until very soft and golden, at least 15 minutes. Meanwhile, butter each toast generously on one side; in a small pot, bring 1 1/2 quarts of water and the tbs. salt to a boil.

Assemble the soupe: in the bottom of a large casserole or pot (I was originally planning to use my 5qt enameled cast iron, but made the very wise decision of upgrading to my large 10qt stainless steel pot. I made 1 1/2 times the recipe, however; the recipe as written calls for a 5qt pot), arrange a layer of 1/3 of the toasts. Top with 1/3 of the non-reserved cheese, and 1/3 of the onions. Spread with 1/3 of the tomato puree. Continue in the same fashion for two more layers, topping with the reserved 1/2 cup of cheese (I found that I needed more).

Add the broth: using a large ladle, slowly pour the hot water down the sides of the pot. You may need more or less water depending on the size of your pot, but the goal is to fill the pot with broth just up until the final layer of cheese. My soupe took surprisingly little water at first, so I made little tunnels with the handle of a wooden spoon around the edge of the pot to help make space for a little more water. I also shook the pot a bit, gave it some to settle and think about whether or not it was moist enough. Eventually, I decided the soupe was content with its broth/bread/onion/cheese/butter/tomato ratio, and simmered it on the stove over medium heat for 30 minutes. After this, bake the soupe in the 350 degree oven for an entire hour. Remember, "The soup is ready when the surface looks like a crusty, golden cake and the inside is unctuous and so well blended that it is impossible to discern either cheese or onion..." Each serving should include a bit of crust and a bit of the gooey unctuousness.


*Unless of course you are a master French Onion Soup Eater. Which I am, thanks to the many New Year's Eves of the Meyer family specialty. I have absolutely crafted the art of F.O.S. consumption, such that every bowl I eat ends not with broth, but with a perfectly balanced bite of bread, broth, onion.