Prepare a non-stick bundt pan with shortening and then spray liberally with non-stick cooking spray, set aside.

Preheat oven to 350.

In large bowl mix together with hand mixer your cake mix, eggs, oil, buttermilk and sour cream and pour into prepared baking dish.

Bake in oven for about 30-40 minutes or until center is set and toothpick comes out clean.

Let cool in pan for about 25 minutes before turning out onto cooling rack to cool completely.

Once cool in another bowl beat together your butter, marshmallow fluff, vanilla and salt for about 2 minutes or until fluffy.

Gradually add in your powdered sugar until combined.

Then add 1/4 cup of heavy cream and continue to mix until incorporated and fluffy, set aside.

Cut your cake in half horizontally removing the top and setting aside.

Spread your marshmallow filling in the bottom half of the cake until you reach about 1/2 inch from edge. Smooth out top then replace the top of the cake.

In a bowl add your chocolate chips.

In another small bowl add your heavy cream and heat in microwave for about 1-2 minutes or until just starting to boil.

Pour over your chocolate chips and cover and let sit for about 5 minutes, then remove and stir until ganache is formed.

Pour over cake letting drip down sides.