Instructions

For the cake: 

1. Preheat oven to 350°F. Coat three, 8- inch cake pans with cooking spray. Line the bottom of the pans with rounds of parchment paper coat with cooking spray.
2. In a large bowl whisk together the all-purpose flour, graham flour, baking powder, baking soda and salt. Set aside.
3. In the bowl a stand mixer fitted with the paddle attachment mix the butter, both sugars, oil and honey for 2 minutes on medium speed for 2 minutes, scraping the sides of the bowl as necessary.
4. Add in the eggs and vanilla, and continue mixing for 1 more minute.
5. Reduce the speed to low and add one-third of the flour mixture, followed by half of the milk, beating after each addition. Repeat this step. End with a final addition of the flour mixture. Once all the ingredients are incorporated mix for an additional 30 seconds, until the batter is smooth.
6. Divide the batter equally between the 3 prepared pans.
7. Bake the cakes for 20-25 minutes, until center is set and a toothpick inserted in the middle comes out clean.
8. Allow the cakes to cool in the pans for 10 minutes, then invert them onto a wire rack to cool completely before frosting, peeling off the parchment paper.

For the toasted marshmallow buttercream:

1. In the bowl of a stand mixer fitted with the paddle attachment beat the butter on one minute until smooth. Turn the speed to low and slowly mix in the powdered sugar. Add in the milk and continue mixing until smooth. Set aside.
2. Turn the oven to broil. Line a large baking sheet with parchment paper and spread the marshmallows out in an even layer. Place the pan under the broiler for 30- 45 seconds until they are browned and puffed. Watch closely because they will burn very quickly. Immediately scrape the marshmallows into the butter mixture and beat until smooth. There will be bits of toasted marshmallows throughout the frosting; this is ok.
3. The frosting will be warm due to the broiled marshmallows, so allow it to cool completely (15-20 minutes) before spreading on the cake.

For the milk chocolate ganache:

1. Place the chocolate in a heat-proof medium bowl.In a small saucepan, heat the heavy cream over medium heat until it starts to steam, stirring constantly. (Alternatively, you can heat the cream in the microwave until very hot) Immediately pour the hot cream over the chocolate and stir until the chocolate is melted. Allow this to cool for 10-15 minutes, until the chocolate is thickened slightly.
2. To assemble the cake, frost the top of each cake layer with equal portions of the buttercream. Place the bottom layer onto a cake plate. Pour one-third of the ganache mixture on top of the frosting and spread it to the edge, using an off- set spatula or spoon. Place the next cake layer on top of the chocolate and repeat the process. Finally place the last cake layer on. If desired, garnish with graham cracker pieces and mini marshmallows. Drizzle the remaining ganache on top.

Store airtight until ready to serve. Keep cake airtight at room temperature for up to 2 days.