Woodsy and wild, with a green and earthy aroma. The sourness of sorrel and bitterness of the endive are offset by the sweetness of balsamic vinegar and walnuts.
Toast nuts in preheated 375-degree oven (or toaster oven) for 5 minutes, until barely crisped. With a towel rub off as much of the husks as possible. Cool and chop in coarse pieces; reserve.
Combine vinegars, sugar, and salt; mix. Gradually beat in the oils. Set aside.
Strip off and discard sorrel stems. Cut leaves in narrow strips. Trim bases and cor