Marble Loaf Cake with Chocolate Buttercream
I love a good slice of marble cake - it's the best of both worlds! This loaf cake is the perfect-sized treat if you're in the mood for some classic marble cake, but don't want to make a full cake. It's buttery, full of yummy flavor, and is topped with decadent chocolate buttercream. If you're crazy about cake, you'll love this marble loaf cake!
Ingredients
For the Marble Loaf Cake
- 2 cups all-purpose flour
- ½ tsp salt
- 2½ tsp baking powder
- 1 cup unsalted butter (room temperature)
- 1¼ cup granulated sugar
- 1 tsp vanilla extract
- 3 large eggs (room temperature)
- ½ cup full-fat buttermilk (room temperature)
- 4 tbsp Dutch-processed cocoa
- 1 tbsp hot water
For the Chocolate Buttercream
- ¼ cup chopped dark chocolate
- 6 tbsp unsalted butter (room temperature)
- ¼ tsp vanilla extract
- ¼ tsp chocolate extract (optional - my favorite is linked below)
- pinch of salt
- ¾ cup powdered sugar
- 1-2 tbsp heavy whipping cream (use more or less depending on how thick you want your frosting to be)
Instructions
For the Marble Loaf Cake
- Preheat oven to 350°F and line a standard-sized loaf pan with parchment paper, leaving enough overhanging on the sides to pull the bread out. Spray with non-stick cooking spray and set aside.
- In a medium mixing bowl, whisk the flour, salt, and baking powder together. Set aside.
- In a large bowl, use a hand mixer to beat the butter and sugar on medium-high speed for 3 minutes until it becomes fluffy and light.
- Add in the vanilla and eggs and beat on medium-high until incorporated. Scrape down the sides of the bowl as needed.
- Add in ½ of the dry ingredients and ½ of the buttermilk. Using a spatula, gently fold into the wet ingredients until just incorporated. Add in the remaining dry ingredients and the rest of the buttermilk and gently fold until just combined.
- Divide the batter in half and place in two separate bowls. Add the sifted cocoa powder and hot water to one bowl. Gently fold with a spatula until combined.
- Using two 2 oz. cookie scoops (2 tbsp. cookie scoops), drop each batter into the pan, alternating with chocolate and vanilla. Repeat until all of the batter is used.
- Using the end of a knife, gently swirl the batters together but do not overmix.
- Bake for 80 - 90 minutes, covering with foil in the last 20-30 minutes of baking so that the top does not burn. Loaf cake is done when a toothpick inserted into the center comes out with a few moist crumbs.
- Cool on a wire rack in the pan before frosting.
For the Chocolate Buttercream
- In a small pan over low heat, melt the chopped dark chocolate. Stir frequently and watch the chocolate so that it does not burn. Once melted remove from the heat and set aside to cool.
- In the bowl of a stand mixer fitted with the paddle attachment, or in a large bowl with a hand mixer, beat the butter on medium-high speed for 3-5 minutes, or until it becomes very pale and fluffy.
- Reduce mixer to low speed and gradually add the powdered sugar. Increase speed to medium-high and beat the powdered sugar and butter together until smooth, about 2 minutes.
- Add the vanilla, chocolate extract, and salt and beat on medium speed until combined. Scrape down the sides of the bowl as needed.
- Add the cooled, melted chocolate to the mixing bowl and beat on low speed until combined. Increase speed to high and beat until light and fluffy. Add in 1 tbsp. of heavy cream at a time if frosting is too thick. Frost cooled cake and enjoy!
Notes
- Cake can be stored at room temperature for 3 days
- Eggs - increase to 4 large eggs
- Flour - increase by 2 tbsp.
- Baking Powder - decrease to 1¼ tsp.
- Oven Temperature - increase to 360°F
- Baking Time - decrease by at least 5 minutes
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