Spread mayonnaise on both sides of 2 slices white sandwich bread. With medium heart-shaped cookie cutter, cut centers from bread. In 12-inch nonstick skillet, melt butter on medium. Add bread (and centers) to skillet. Cook 5 minutes or until golden brown. Turn bread over. To each heart-shaped hole, add 1 large egg; sprinkle eggs with pinch of salt and pepper. Reduce heat to medium-low. Cook 5 to 7 minutes, or until whites are set. Sprinkle with finely chopped capers and herbs (such as parsley, chives or basil) if desired.