1 Vidalia onion (available seasonally at specialty produce markets and some supermarkets), sliced very thin
Directions
In a small bowl stir together the mayonnaise, 1/4 cup of the parsley, the tarragon, the lemon juice, the Tabasco, and salt and pepper to taste. Spread one side of the bread slices with the mayonnaise, arrange the onion slices evenly on half the bread slices, and top them with the remaining bread slices. Press the sandwiches together gently, trim the crusts, and cut the sandwiches into quarters. Put the remaining 1/4 cup parsley in a shallow bowl and dip the edges of the sandwich quarters in the parsley.
