Decadent Hot Chocolate Layer Cake Recipe

Tender chocolate cake layers enriched with hot cocoa mix, filled with a white chocolate buttercream studded with marshmallows and a dark chocolate ganache drizzle, frosted in hot chocolate buttercream, finished with a white chocolate ganache drip and crowned with a generous pile of marshmallows. This Hot Chocolate Cake was inspired by Brooke Walker of Studio 5’s CHIP cookie of the month flavor, and both the cake and cookie versions celebrate those irresistible winter flavors.

A few months ago I developed a Red Velvet Hot Cocoa Cake with toasted marshmallow filling, which I enjoyed sharing widely, including an appearance on Hallmark Home & Family. For this cake I aimed to echo Brooke’s CHIP cookie as closely as possible: a chocolate base with white chocolate and marshmallows throughout. The result is my Hot Chocolate Cake.

For the cake layers I wanted a rich chocolaty flavor that still let the hot cocoa notes shine through, so I added hot cocoa mix directly to the batter. I use a doctored boxed cake mix approach—substituting the standard eggs, oil, and water with sour cream, buttermilk, extra eggs, vanilla, and a touch of oil—to produce thick, tender layers with deep chocolate aroma and great structure for filling and decorating.

To mimic the white chocolate chips from the cookie, I made a white chocolate buttercream by folding white chocolate ganache into buttercream. The texture becomes almost ice-cream-like and pairs beautifully with marshmallows. Rather than bake marshmallows into the layers or make a separate marshmallow filling, I press whole marshmallows into the white chocolate buttercream while assembling the cake so they remain visible and delightful in each slice.

I boosted the filling with a dark chocolate ganache drizzle over the marshmallow-studded buttercream for extra contrast and an addictive layer of chocolate richness.

The hot chocolate buttercream is the cake’s finishing touch. Instead of using only cocoa powder, I substitute half of the cocoa with hot chocolate mix, which gives the buttercream that distinctive hot cocoa flavor and sets it apart from a standard chocolate buttercream. Whip the buttercream well so the hot chocolate granules fully incorporate; if needed, dissolve the hot cocoa in a little warm cream before adding to avoid any grainy bits.

For the white chocolate drip I use “Very White” Wilton candy melts to match the appearance of the marshmallows and achieve a clean, bright drip. Gently warm the melts with heavy cream—short bursts in the microwave and careful stirring—to avoid scalding or seizing, and stir until smooth.

When topping with marshmallows, add them while the white chocolate ganache is still slightly tacky so they adhere without sliding off. If transporting the cake, consider adding marshmallows on site for best results. For clean slices, chill the cake and use a hot, sharp knife when cutting.

We loved this cake and are excited to share it with Brooke and the Studio 5 team. If you make it, I’d love to see your version—tag @bakingwithblondie or use #bakingwithblondie on Instagram.