Heat oven to 350 degrees. Grease bottom of a 9 x 13 inch pan.
Prepare cake mix according to package directions (Betty Crocker calls for the water, oil, and eggs as listed above).
Bake for 30 to 35 minutes or until done.
Using a fork or spoon handle, poke holes over the entire cake after taking it from the oven.
Pour sweetened condensed milk over the cake, letting it soak into the holes.
The pour the hot fudge sauce over the top of the whole cake and spread gently covering all of the cake. You may need to soften the hot fudge slightly in the microwave if it's too thick to pour or spread.
To make the frosting, beat together butter, milk, powdered sugar, peppermint extract, and green food coloring until smooth.
Spread over the cooled cake.
Sprinkle on chopped Andes Mints and refrigerate for at least an hour before serving.
Notes
Hot fudge is a little bit rich, however it tastes amazing with this cake. If you are looking for a simple and delicious alternative to hot fudge, we recommend using Hershey’s Chocolate Syrup.