Cut bread into slices a quarter of an inch thick, then with a biscuit-cutter about three inches in diameter stamp it into circles. Moisten the circles of bread with milk, but do not use enough to cause them to fall apart; then spread them with any jam or preserve and place two together like a sandwich. Place them in a frying-pan with a little butter, and saute them on both sides to a delicate color. Sprinkle with powdered sugar and serve very hot. A sabayon or other sauce can be served with them if convenient, but it is not essential.