Bob Cannard Jr., a farmer in Sonoma Valley who grows produce for Chez Panisse and other high-end restaurants but no longer sells at local markets, came to my table, scooped up some of the sauce I had just made, drizzled it over a sandwich, and handed it to me.
Made on a whole wheat hot dog bun from Alvarado Street Bakery, it had strips of cucumber, sweet golden tomatoes, and thin slices of baby torpedo onions. It was unforgettable, and I’ve used the sauce as a condiment on sandwiches ever since. Traditionally, the sauce itself is the centerpiece of the Italian meal known as bagna cauda, in which seasonal vegetables and chunks of good bread are served alongside for dipping. You can think of this sandwich as a hand-held version. The anchovies are an essential ingredient in the sauce, but vegetarians can omit them and still have a great sandwich.