Drain peaches, reserving ⅔ cup juice. Chop peaches into small pieces.
In a large bowl, dissolve gelatin and sugar in the boiling water. Stir in reserved juice. Chill until slightly thickened. Stir extract into whipped topping; gently fold into gelatin mixture. Fold in peaches.
Pour into an oiled 6-cup mold. Chill overnight. Unmold onto a serving platter; garnish with peaches if desired.
