Step 1

Preheat oven to 350 degrees F. Grease 13x9x2-inch baking pan. In large bowl, stir together flour and granulated sugar. Set aside.

Step 2

In medium saucepan, combine butter, cola, and cocoa powder. Cook and stir over medium heat until butter melts. Pour over flour mixture. Add eggs, buttermilk, baking soda, and vanilla; mix well. Stir in marshmallows. Pour into prepared baking pan.

Step 3

Bake for 30 to 35 minutes or until a wooden toothpick inserted near center comes out clean. Cool cake in pan on wire rack.

Step 4

Spread Cocoa-Cola Frosting over cake. Sprinkle with pecans and marshmallows, if desired.