This tangy sauce is traditionally served with veal, but we also love it with cold poached chicken, roast pork, or grilled or roasted vegetables.
Combine in a food processor or blender:
Process until smooth, 30 seconds to 1 minute, scraping down the sides as needed. Transfer to a bowl, cover, and refrigerate. To serve, thinly slice the cold meat or chicken and arrange, overlapping, on a platter. Pour the sauce over and sprinkle with: