Dissolve gelatin in boiling water. Add cold water.
Chill until partially set; whip until light and fluffy. Add lemon juice and sugar. Whip chilled milk and fold into gelatin mixture. Add food coloring if desired.
Line bottom of 9"x13" pan with half the crumbs.
Pour gelatin mixture over crumbs. Add rest of crumbs on top of gelatin. Chill until firm.
Not a NESTLÉ®-tested recipe.