Fennel and Onion Soup

This soup starts with big mounds of sliced fennel and onions, but don’t worry—these vegetables will reduce dramatically as they slowly cook down, turning brown and sweet and developing a deep, rich flavor that you will love.–Anna Thomas

Fennel and Onion Soup Recipe

  • Quick Glance
  • 20 M
  • 1 H, 40 M
  • Serves 6 to 7


  • 3 medium fennel bulbs, trimmed
  • 4 large yellow onions
  • 4 tablespoons olive oil
  • 1 bay leaf
  • 1 teaspoon sea salt, plus more to taste
  • 1 cup dry wine, red or white
  • 6 cups homemade light vegetable stock
  • Freshly ground black pepper
  • Cheese croutons, optional garnish


  • 1. Trim and clean the fennel bulbs, quarter them lengthwise, and slice them thinly crosswise. Peel the onions and do the same, cutting them in quarters lengthwise, then slicing thinly.
  • 2. Heat 2 tablespoons olive oil in each of two large saute pans. Add the fennel to one and the onions and bay leaf to the other, each with 1/2 teaspoon salt. Cook the vegetables slowly over medium-low heat, stirring pretty often, until they are all a gorgeous golden brown. This will take forever—45 minutes to 1 hour—but you can be doing other things as long as you cast an eye on them now and then and give them a stir.
  • 3. When both the fennel and onions are nicely softened and browned, add the wine to the fennel to deglaze the pan and then add the fennel to the onions. Continue cooking and stirring until the wine has cooked away and the vegetables are sizzling. Combine the caramelized fennel and onions with the broth in a soup pot and use a little of the broth to deglaze the pan, so that all the lovely brown bits go into your soup. Simmer the soup gently, covered, for another 20 minutes to blend all the flavors. Add pepper to taste.
  • 4. Taste, and correct the seasoning with a little more salt if needed.

Another way

  • This soup is wonderful with a cheese crouton on each serving, the way traditional onion soup is served. Ladle the soup into ovenproof bowls or individual casseroles, place a piece of toasted French bread on top of each serving, and cover each toast with about 1 ounce grated Parmesan or Gruyère cheese or any sharp, aged cheese that you like. Put the bowls on a baking sheet and slide them under a broiler for a few minutes, just long enough to melt and brown the cheese.
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Recipe Testers Reviews

Eydie Desser

Sep 17, 2009

This soup is very easy and time consuming and so worth it! I was concerned about making an onion soup with vegetable broth as opposed to the traditional chicken or beef broth, but have no fear, this fennel and onion soup is delicious. I made my own vegetable broth, which is key. After tasting several store bought vegetable broths, a homemade one makes all the difference.

Be patient when cooking the fennel and onions and definitely follow the directions to cook the vegetables slowly on medium-low heat. You will be rewarded with beautifully caramelized and buttery tasting (without the butter) results that all go into making this healthy onion soup a Testers Choice recipe.

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