Easy Lime Pie
["1 (14 fluid oz.) can sweetened condensed milk", "1 tsp. grated lime rind", "1/3 c. lime juice", "1 (8 oz.) container Cool Whip, thawed", "2 or 3 drops green food coloring (optional)", "1 prepared 8 or 9-inch graham cracker crumb crust"]
["Combine milk, lime rind and juice in a large bowl. Fold in whipped topping and food coloring, blending well. Spoon into crust and chill 2 to 3 hours."]
["condensed milk", "lime rind", "lime juice", "coloring", "graham cracker crumb crust"]