There are some fake recipes for Caesar salad soup out there using things like fennel and celery that have no business in a Caesar salad. I wanted to make a proper version: a lettuce soup with a classic Caesar dressing, croutons and Parmesan.
This is a recipe in three parts. Let's start with the garnishes.
2 large cloves garlic
2 Tablespoons extra virgin olive oil
2 slices of white, French or Italian bread
1. Crush garlic and add, with a large pinch of salt, to olive oil. Let rest at room temperature for at least five minutes.
2. Cut bread into large chunks and lightly toast
3. Strain oil into frying pan. Heat over medium high heat until sizzling. Put the garlic back in the bowl. You're going to add it to the soup later.
4. Add bread to pan and fry, tossing frequently, until the oil is all soaked up and the bread is crispy, golden brown and delicious. Sprinkle with a bit more salt.
1 1/2 Tablespoon of Parmesan per crisp (Use a young cheese as an aged Parmesan doesn't have enough moisture to melt. It will just toast and after twice as long in the oven as the recipe says you'll get frustrated, mix it into the leftover grated Ementhal you have in the fridge, and finish it off in a frying pan. You'll get a nice texture, but the end result won't have the right flavor to go with the Caesar salad soup.)
1. Finely grate cheese into little piles onto a cookie, preferably lined with parchment paper or a silpat.
2. Bake at 325 degrees F for ten to twelve minutes. Alternatively, you can fry the grated cheese in a non-stick pan over medium low heat for several minutes, flipping when the bottom is browned. The crisps in the oven don't need to be flipped, but it wouldn't hurt to turn the pan around halfway through.
3. The crisps will harden up quickly, but just out of the oven you can roll them around a rolling pin or drape them over the bottom of a glass or, if you're really good, make an origami swan.
Caesar Salad Soup
1 pound (about 8 cups) romaine lettuce
2 cups chicken broth
1 cup water
2 1/2 Tablespoons extra virgin olive oil
juice of 1/2 lemon
3 drops Worcestershire sauce
2 anchovy fillets, minced
coarse ground black pepper to taste
1. Tear up, wash and dry lettuce.
2. Boil the broth and the one cup water, add lettuce and a sprinkle of salt, turn down heat, cover and simmer 10 minutes.
3. Heat a small pot of water to a boil, turn down to a simmer and cook egg for one minute. (I overcooked the egg a little, but it's all getting blended so no big deal.)
4. Mix the garlic from the croutons with olive oil, lemon juice, Worcestershire sauce, anchovy and pepper.
5. I let everything sit for a half hour to cool so I didn't have to worry about the egg getting cooked. If you intend to serve the soup hot you'll need to temper the dressing before adding it to the soup by mixing in spoonfuls of the hot soup.
6. Mix egg into dressing.
7. Blend soup until smooth. Drizzle in dressing while blending.
8. Serve with garlic croutons and grated Parmesan optionally in crisp form.
The soup was light, smooth and velvety. Possibly a bit too light; I think the egg white was holding on to a bit of incorporated air. I liked the somewhat less smooth texture of the plain lettuce soup a bit better, but I blended that less, too. As I didn't have to worry about adding any extras. I think next time I might blend the soup to the texture I want and then mix in the dressing by hand.
The primary flavors were the lettuce and lemon with accents of anchovies and olive oil. Nicely complex and balanced, but it was mild and a bit overpowered by the intensity of the croutons and the cheese crisp. Grating Parmesan on top instead will help with the balance. The croutons really were the best bit so I can't in good conscience tell you not to use them, but maybe smaller croutons would work better. I'll have to experiment with the leftovers.