Chocolate Marshmallow Layer Cake

Name: Chocolate Marshmallow Layer Cake
Prep time: 1 h
Cook time: 25 min
Total time: 1 h 25 min
Cuisine: American
Ingredients: 2 cups granulated sugar; 1 3/4 cups all purpose flour; 3/4 cup unsweetened cocoa powder; 1 1/2 teaspoons baking powder; 1 1/2 teaspoons baking soda; 1 teaspoon salt; 2 eggs; 1 cup milk (I prefer whole milk); 1/2 cup vegetable or canola oil; 2 teaspoons pure vanilla extract; 1 cup boiling water; 1/2 cup unsalted butter (softened); 1 1/4 cups powdered sugar; 1/2 teaspoon pure vanilla extract; 1 tablespoon milk; One 7-oz container marshmallow creme/marshmallow fluff; 3/4 cup unsalted butter (softened); 3 1/2 cups powdered sugar; 1/4 whole milk ((plus more if needed)); 1 1/2 cups mini marshmallows; 3 tablespoons chocolate chips; 1 teaspoon milk