Heat olive oil over medium-low heat, stir in the dark green part of the leeks, and sauté for 5 minutes. Add the rest of the leeks along with the fennel, zucchini, and garlic, cover, and let cook, stirring occasionally, for 15-20 minutes, until soft.
Add fennel seeds and stock, increase heat to medium, and cook another 10-15 minutes.
Let the soup cool a bit, then put vegetables* in the blender along with a cup or so of the liquid and process until smooth.
Return to the saucepan with the rest of the liquid and stir well. Season with salt and pepper and heat until just about to boil.
*You might like to save a few T for garnish.
The original recipe called for two egg yolks to thicken the soup, but I didn’t see the point, so I left them out too, and the consistency was perfect.
This recipe, originally called "Fennel bisque with zucchini and leeks," or Soupe au Fenouil in French, was adapted from The Vegetarian Bistro: 250 authentic French regional recipes, by Marlena Spieler – read my review.
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