FOR THE CAKE
Cooking spray, for pan
Cocoa powder, for dusting pan
1 box Devil’s food cake mix, plus ingredients called for on box
1 jar hot fudge, warmed (reserve 2 tbsp. for drizzling)
1 c. chopped Andes mints
FOR THE FROSTING
1 c. (2 sticks) butter, softened
2 1/2 c. powdered sugar
1 tbsp. whole milk
1 tsp. peppermint extract
1 tsp. pure vanilla extract
5 drops green food coloring
Preheat oven to 350º, grease a 9″-x-13” pan with cooking spray and dust it with cocoa powder. Prepare cake batter according to package directions, then pour into prepared pan and bake according to package directions, 23 to 25 minutes.
Poke holes all over the cake with the bottom of a wooden spoon and drizzle with all but 2 tablespoons hot fudge.
Make frosting: In a large bowl using a hand mixer, beat butter until smooth. Add powdered sugar, milk, and peppermint and vanilla extracts and beat until combined. Add food coloring until you reach your desired color.
Spread frosting on the cake and top with Andes mints. Drizzle with reserved hot fudge.