1 Tbsp.chopped fresh tarragon, plus more for garnish
2 Tbsp.heavy whipping cream, plus more for drizzling
Instructions:
Assemble all your ingredients.
In a large saucepan over medium-high heat, melt butter until sizzling. Cook leek and garlic, stirring frequently, until softened for about 4 minutes. Add stock, potato, and salt. Let it simmer over medium-high heat until potatoes are tender, about 7 minutes without stirring.
Add watercress to the pan and cook until wilted, approximately 2 minutes. Take the pan off the heat and fold in the fragrant tarragon.
Blend watercress mixture and cream until smooth for about 20 seconds. Pour into 6 bowls, add a swirl of cream, and sprinkle with a bit more tarragon for garnish.