Mississippi Mud Cake

Directions

1. Heat the oven to 350 degrees. Coat a 13x9-inch pan with nonstick cooking spray. Whisk the flour, cocoa, baking powder, salt and baking soda in a medium bowl. Beat the sugar and 3/4 cup softened butter in a large bowl at medium speed for 3 minutes or until light and fluffy.
2. Beat in 2 cups sour cream. Beat in the eggs, one at time until blended. Beat in the vanilla. Add in the flour mixture and stir to incorporate. Spread the mixture into the pan.
3. Bake for 40 to 45 minutes or until a toothpick inserted in the center comes out clean. Cool on a wire rack for 15 minutes. Meanwhile, combine the chocolate chips and 1/3 cup butter in a medium saucepan.
4. Cook over medium-low heat until melted, stirring frequently. Stir in 1/2 cup sour cream. Remove from the heat and stir in the powdered sugar until smooth.
5. Sprinkle 2 cups of the marshmallows and 1/2 cup of the pecans over the warm cake. Pour the warm frosting over the marshmallows and pecans and gently spread over the cake. Sprinkle with the remaining 1 cup marshmallows and 1/4 cup pecans.