Ingredients

• 5 tablespoons unsalted butter
• 1 leek, chopped
• 1 onion, chopped
• 1 carrot, chopped
• 1 teaspoon dried tarragon
• 1/2 teaspoon dried thyme
• 1/4 cup all-purpose flour
• 1 cup dry white wine
• 6 cups chicken stock
• salt to taste
• 1/4 teaspoon freshly ground white pepper
• 1 head cauliflower, broken into small florets
• 1 cup milk
• 1 cup heavy whipping cream
• 2 1/2 cups shredded Swiss cheese (optional)