Ingredients

5 Jerusalem artichokes, washed and very thinly sliced 

3 sprigs fresh tarragon, picked of leaves, stems reserved 

1/3 cup sherry-wine vinegar 

Coarse salt and freshly ground pepper 

2 small shallots, minced 

2/3 cup grapeseed oil (optional) 

Preparation

In a small saucepan, combine Jerusalem artichokes, tarragon stems, and half of the vinegar. Add enough water to cover by about 1/2 inch. Season with salt and pepper. Bring to a boil over high heat, reduce to a simmer, and cook until tender, about 25 minutes. Drain, and place in a blender. Add just enough of the cooking liquid to puree until very smooth. Add reserved tarragon leaves, remaining vinegar, and shallots. Pulse to combine. Add either grapeseed oil or a little of the cooking liquid depending on the desired consistency.