Instructions

For the Chocolate Mocha Cake

1. Preheat the oven to 360 degrees F. Spray three 8-inch or four 6-inch pans with nonstick spray, line the bottom of the pans with parchment paper and spray again. Set aside.
2. Combine the flour, sugar, cocoa, baking soda, baking powder, and salt into the bowl of an electric mixer fitted with a paddle attachment and mix on low speed until combined.
3. In another bowl, combine the buttermilk, oil, eggs, hot coffee (or water), vanilla and coffee emulsion.
4. With the mixer on low speed, slowly add the wet ingredients to the dry, scraping the bottom of the bowl with a rubber spatula.
5. Pour the batter evenly into the prepared pans, and bake for 16-18 minutes, until a toothpick inserted in the center of the cake comes out almost clean. (A few crumbs on the toothpick is definitely ok!).
6. Cool in the pans for 10 minutes, then turn them out onto a cooling rack and cool completely.
7. Level each cake layer with a cake leveler. Use immediately or wrap in plastic wrap twice and freeze for up to a week. If you'd like to freeze the cake layers longer than a week, also wrap each layer with tin foil. 

For the Mocha Chip Filling

1. Place the marshmallows on a cookie sheet lined with parchment paper and sprayed with nonstick cooking spray. Place on the middle rack of the oven, and broil the marshmallows until golden brown on top, about 30. Keep your eye on them!
2. In the bowl of a stand mixer fitted with the paddle attachment, combine the butter, powdered sugar and salt, and beat on low until blended. Add the vanilla and coffee emulsion and mix on medium speed for about three minutes
3. With the mixer on low speed, add the marshmallow cream and (cooled) toasted marshmallows, and mix for about one minute. 
4. Can be stored in an airtight container for up to a week in the refrigerator. Bring to room temperature before using on the cake.

For the Salted Caramel

• Mix the sugar, water and corn syrup in a small saucepan over medium heat.
• Bring the mixture to boil, but DO NOT STIR! (Stirring encourages crystallization). Let the mixture cook until it turns to a golden brown/amber color. It happens quickly, so keep an eye on it.
• Remove the caramelized sugar syrup from the heat and very slowly stir in the cream, pouring it in little by little, to temper the cream and sugar syrup. If you pour it in all at once, your sugar will turn into hard candy. You can start adding more and more as you go along.
• Once the cream is mixed in, add the salt, and vanilla. Stir to combine and then set aside to cool to room temperature before using.    

For the Frosting

1. In the bowl of a stand mixer fitted with the paddle attachment, beat the butter until smooth and light in color, about 2 minutes.
2. With the mixer on low speed, gradually add the powdered sugar, one cup at a time, followed by the salt, vanilla and coffee emulsion.
3. Add the heavy cream and then turn the mixer to medium-high speed and beat for 5 minutes.
4. Frosting can be store in an airtight container in the refrigerator for a week or frozen for up to a month.
5. When you're ready to frost the cake, bring the frosting back to room temperature and mix by hand with a wooden spoon to push out all of the air pockets. 

Assembly

1. Place the first cake layer, top side (crumb side) up on a cake board, set on a turntable. Spread 1/3 of the marshmallow filling on top of the cake layer. Drizzle with salted caramel and sprinkle with mini chocolate chips. Place the next cake layer on top and repeat with filling, caramel and chocolate chips.
2. When you get to the final cake layer, place it top side (crumb side) down. Cover the entire cake with a thin coat of frosting and freeze for 10 minutes. This is called a crumb coat and will lock in the crumbs of the cake so you get a much cleaner looking cake.
3. When the crumb coat is set, continue frosting the cake with the remaining frosting and garnish with caramel, chocolate chips, coffee beans and Mocha Chip SmashMallows.