First make the celery walnut oil: Bring a small saucepan of water to a boil. Blanch the celery leaves for 1 minute in the boiling water and scoop them out with a slotted spoon. Let cool and squeeze out the water. Pat dry with a clean dish towel.
Put the squeezed-out celery in a deep container and pour the two oils on top. Season with salt and pepper. Puree with a hand blender until completely smooth. Strain through a fine sieve and discard the solids. Keep in a clean bottle until serving.
Shave the almonds with a fine vegetable slicer, keeping your fingers pressed flat on the almonds. It’s relatively easy and provides a flavor and texture very different from plain sliced almonds or chopped smoked almonds. Set aside until ready to serve.
Make the soup: Heat the olive oil in a large saucepan over medium heat. Add the parsnips, potatoes, and onion and sauté until the onion is soft and translucent, about 7 minutes. Stir occasionally. Add the garlic, the spices, and ginger. Sauté for 1 minute.
Add the stock and apple and let the soup simmer for about 20 minutes over low heat until the vegetables are tender.
Puree the soup with a hand blender, or in batches in a regular blender, into a smooth crème. If needed, add salt and pepper and season the soup with lemon juice.
Once it’s cooled, keep covered in the fridge until ready to serve, or move on straight away.
Reheat the soup. Divide among four to six bowls. Drizzle the celery oil on top and sprinkle with pepper and the shaved almonds.
© 2018 All rights reserved. Published by Abrams Books.