Apparently James Beard served these sandwiches to Pepin one Sunday morning in the mid-'60s. (Hangover food?) Interesting enough for a party, cut them into smaller pieces for elegant hors d'oeuvres. The is adapted from The Essential Pepin, by Jacques Pepin (Houghton Mifflin Harcourt 2011).
Makes 4 servings
8 thin slices firm white bread
6 tablespoons mayonnaise
1 tablespoon Dijon mustard
4 1/8-inch thick slices mild onion, such as Vidalia or Wall Walla, about 3 1/2 inches in diameter
1/4 cup minced fresh chives
Arrange the bread slices next to one another on a work surface. Using a glass or a round cutter, cut circles as large as possible out of the slices.
Mix the mayonnaise and mustard together. Spread each bread circle with 2 teaspoons of the mixture. Place an onion slice on 4 of the bread rounds (it should cover them to the edges). Top with the remaining bread circles. Press slightly to make them adhere.
Holding each sandwich in your hand, spread some of the remaining mayonnaise mixture on the outside edges, then roll the edges in the chives until coated. Press lightly to make the chives stick.