lemon cake frosting

Lindsay Hall's celebrating the month of september babies and the deans made many different cakes, along with other kinds of goodies. My favorite, as you can tell is this lemon cake. She makes a really wicked frosting that's ~~~ what can i say? yummy! She graciously shared with me the lemon frosting recipe:
Ingredients:
1. 1 can sweetened condensed milk
2. 1/2 cup lemon juice
3. few drops of yellow food color ( depending on how yellow you want it to be)
4. 1 cup stiffly whipped cream ( or cool whip)
Directions: Mix # 1-3 well and stir in 4. Refrigerate over night or for 3-4 hours. Do not remix it once it has been refrigerated. Spread it over the cake. Slice lemon or lime to decorate
(x3 for 2 large pans)