To dress up this already-pretty soup even further, bake disks of puff pastry to place atop each portion for serving.
- 4 ounces thick-sliced bacon, cut into 1/4-inch dice, for garnish
- 1 medium yellow onion, finely chopped (about 1 cup)
- 1 1/2 pounds (about 2 medium) celery root (celeriac), peeled and cut into 1/4-inch dice
- 3 cups seafood broth or three 8-ounce bottles clam juice
- 3 cups water
- 1/2 pound tiny new potatoes, scrubbed, each cut in half
- 2 pounds skinless salmon fillet (preferably wild-caught), cut into 1-inch chunks
- 1 1/2 cups heavy cream
- 3 tablespoons unsalted butter, at room temperature
- 3 tablespoons flour
- 3 tablespoons finely chopped dill
- 2 tablespoons finely chopped flat-leaf parsley
- Finely grated zest and freshly squeezed juice of 1 lemon (1 teaspoon zest and 2 tablespoons juice)
- 1/4 teaspoon kosher salt
- Ground white pepper
Line a plate with a few layers of paper towels.
Cook the bacon in a large skillet over low heat until crisped; transfer to the paper-towel-lined plate to drain. Pour off all but 2 tablespoons of fat from the skillet; increase the heat to medium-low.
Add the onion to the skillet and cook for about 3 minutes, stirring, until softened. Add the celery root, cover the skillet and cook, stirring occasionally, until tender, about 15 minutes. Turn off the heat.
Combine the broth or clam juice and the water in a large, heavy saucepan over medium-high heat. Bring to a boil and add the potatoes, then reduce the heat to medium and cook for 8 to 10 minutes or until the potatoes are tender. Use a slotted spoon to transfer them to a platter.
Add the salmon to the saucepan; reduce the heat to low and cook gently for about 4 minutes, just until the fish is firm; transfer the salmon to the platter with the potatoes.
Increase the heat to medium-low; add the cream to the saucepan and cook for 15 to 20 minutes, stirring frequently, until the mixture has reduced by about one-quarter. Watch closely so the mixture does not boil over.
Use a fork to blend the butter and flour in a small bowl to form a smooth paste; whisk it into the saucepan a little at a time to form a slightly thickened soup. Increase the heat to medium; cook for about 3 minutes, stirring, to lose the flour's raw taste.
Stir in the reserved celery root mixture, potatoes and salmon. Cook for about 2 minutes until warmed through, then stir in the dill, parsley, lemon zest and lemon juice. Season with the salt and white pepper to taste.
Divide among individual bowls, preferably warmed ones. Crumble some of the bacon on each portion. Serve hot.
From "Mr. Sunday's Soups," by Lorraine Wallace with Brigit Binns (Wiley, 2011).
Tested by Monica Norton.
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