Ingredients
1 white cake mix baked according to directions. I made mine in a 6-inch pan and reserved a bit of batter for a few cupcakes. This cake would work really well in a 9 X 13 pan.
1 can Borden sweetened condensed milk
1/2 cup of fresh lime juice. . .about 4 small limes
2 cups of whipping cream divided
a few drops of green food coloring if desired
Instructions:
Combine the sweetened condensed milk, the lime juice and 3/4 cup whipping cream.
Set aside 1 cup of filling for the frosting.
Use the end of a wooden spoon to poke holes at 1/2 inch intervals in the cake. .nearly to the bottom but not through the cake. Pour filling over the cake and work into the holes.
Whip the remaining whipping cream until soft peaks form. Add the few drops of green food coloring and the remaining filling and whip together until it is a spreadable consistency.
Frost the cake and chill until serving time.
Source : allrecipes.com