Grasshopper Fudge Cake

My daughter found this in one of my old Betty Crocker calandars, and had marked it with a small green heart. It's been sitting on the fridge for a few months now, and with St Patricks day coming, what better time to make it?  
I changed a few things from the original recipe, as always, but the idea is the same and quite good!

1 (18 ¼ ounce) box Betty Crocker super moist white cake mix

1 ¼ cups water

¹⁄₃; cup vegetable oil

2 teaspoons mint extract

3 egg whites ( ides 3 eggs)

12 drops green food coloring

2 (16 ounce) jars hot fudge topping

8 ounces frozen whipped topping , thawed (I made my own whipped cream)

5 drops yellow food coloring ( didn't use)

Andes mints candies , unwrapped and cut into pieces

* I added 1/2 vanilla bean*

Heat oven to 350F for shiny metal or glass 13x9 pan (or 325F for dark or nonstick 13x9 pan).

Spray bottom only of pan with baking spray with flour.

Make cake mix as directed on box, using water, oil, 1 1/2 tsp mint extract and the egg whites.

Reserve 1 cup batter; stir 3 drops of the green food coloring into the reserved batter and set aside.

Pour remaining batter into pan.

Drop green batter by generous tablespoonfuls randomly in 12-14 mounds onto the batter in pan.

Cut through batters with a metal spatula or knife in S-shaped curves in one continuous motion.

Turn pan 1/4 turn; repeat cutting for swirled design.

Bake 28-33 minutes or until toothpick inserted in center comes out clean.

Run knife around side of pan to loosen cake.

Cool completely, about 1 hour.

Carefully spread fudge topping evenly over the cake.

In medium bowl, stir whipped topping, remaining 1/2 tsp extract, remaining 9 drops of green food coloring and the yellow food coloring until blended.

Spread whipped topping mixture evenly over fudge.

Garnish with candy pieces.

Store covered in refrigerator