Step 1

Heat the oil in a large pot over medium heat. Add the leeks, celery, ¼ teaspoon salt, and cook 5 minutes. Add the mushrooms and cook until soft, 8 to 10 minutes more.

Step 2

Stir in the tamari, wine, garlic, and thyme and cook for 30 seconds to 1 minute, or until the wine has evaporated. Add the broth and the cauliflower.

Step 3

Simmer uncovered for 20 minutes, or until the cauliflower is very soft. Transfer to a blender, add the mustard and vinegar, and blend until smooth. Season to taste and serve with desired garnishes.