Drain peaches, reserving 2/3 cup juice. Chop peaches into small pieces; set aside.
In a large bowl, dissolve gelatin and sugar in 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 additional peaches if desired.