How to: Caramelized Leek, Onion, and Shallot Soup
When the weather gets cold, there is nothing like a rich soup to warm you up. My friend Meredith once commented sautéing onions is the best cooking smell there is. This soup takes that to a whole new level, and the leeks are the star. The leeks are roasted to add smokiness and the onions and shallots are sautéed with butter. Then some vermouth and heavy cream gets introduced and everything comes together.
Servings Prep Time
6 10
Cook Time Passive Time
1.5 hours 40 min
Servings Prep Time
6 10
Cook Time Passive Time
1.5 hours 40 min
Ingredients
Instructions
  1. Preheat the oven to 400°F.
  2. Set a large pot of salted water on to boil.
  3. Trim and clean the leeks: Remove the root and then the tough green end. Halve the leek lengthwise. Spreading the layers apart, rinse thoroughly. Leeks can be very dirty.
  4. Peel the garlic and smash it with the side of a knife.
  5. Dice the onions and the shallots
  6. When the water has boiled, blanch the leeks for about 20 seconds. Then, shake the water off and place in a metal pan. Drizzle with a little olive oil and white wine vinegar. Season with salt, pepper, and thyme. Add the garlic to the pan. Roast in the oven for 10 min.
  7. While the leeks are roasting, in a medium skillet, melt 2 tbsp of the butter over medium heat. Once melted, add the onions. Sauté for 2 minutes and then add the shallots (the moisture from the onions will keep the shallots from burning). Stirring occasionally, cook the onions and shallots for 15 min till soft and golden. (If you have the time, you can do this longer and really caramelize them).
  8. Add a splash of white vermouth to the pan. Once incorporated, you can take the pan off the heat to cool. After a few minutes, add the heavy cream to the onion mixture and stir.
  9. When the leeks are out of the oven and cool enough to handle, chop them into 1 inch (approx) chunks.
  10. In a large pot, melt the remaining 3 tbsp of butter over medium low heat. Once melted, add the flour. Whisk. The mixture will become a paste. Cook the paste, whisking continuously for 3 minutes. Add about 1 cup of the water quickly. Whisking quickly, combine the paste and water until smooth. Gradually add the rest of the water. Then add the onion and cream mixture and the leeks. Add the bay leaf and some thyme. Bring to a boil. Once boiling, reduce the temperature and simmer with the lid partially on for 45 min. Check on the soup while it is simmering. Add more water if the soup is looking too dry.
  11. Turn off the heat and let the soup cool until it is cool enough to purée. Remove the bay leaf. Then purée the soup in a blender. You can use an immersion blender for this but you want it velvety smooth. This texture is more easily achieved with a traditional blender.
  12. Once puréed,return the soup to the pot and season with salt, pepper, thyme (if needed) and lemon juice.
Recipe Notes

Years ago I waited tables in an Irish tea room.  The lady who made the soups (I forget her name but I always remember her soup) was from Dublin and made glorious soups from scratch.  She told me to always add a little lemon juice to cream soups.  Because her soups were so fantastic, I always have.