This Marble Loaf Cake is THE BEST! It's moist, easy, and swirls both chocolate and vanilla into one loaf cake! The cake is so light and fluffy thanks to sour cream and oil, is so simple and made with just a handful of ingredients you likely already have in your kitchen, and takes just 15 minutes to prepare.

If you love this marble effect, check out my Buttermilk Marble Bundt Cake to serve a larger crowd. If you are in the mood for the richest and easiest chocolate cake, might I suggest my Chocolate Sheet Cake recipe or Chocolate Ganache Loaf Cake... any of these will be life-changers!
What Makes This Recipe Work
Chocolate AND Vanilla Loaf Cake- This pound cake has a gorgeous marble effect, combining both chocolate and vanilla batter in a gorgeous swirl pattern.
Moist, Light, and Fluffy- This cake is made with sour cream and buttermilk, making a super tender and light cake.
Loaf Tin- Since this cake is made in a loaf pan, it's easy to bake, decorate, slice, and serve!

Chocolate Marble Pound Cake Ingredients
- All Purpose Flour: You'll need to measure flour properly by using a kitchen scale or by using a spoon to transfer flour to your measuring cups before taking a knife to sweep across the top to level the flour.
- Baking Powder & Baking Soda: Together, these two ingredients create a gorgeous dome and a light and fluffy texture.
- Salt: Salt brings out sweetness in this marble cake and brings out both the vanilla and chocolate flavors.
- Vegetable Oil: This cake is moist as ever thanks to vegetable oil. You can substitute vegetable oil for any unflavored oil.
- Eggs: 2 large eggs at room temperature create a structured cake with great flavor.
- Vanilla Extract: Vanilla extract rounds out the flavor of the cake.
- Sour Cream: Sour cream can be substituted with room temperature greek yogurt to create a tender crumb.
- Buttermilk: Buttermilk is incredibly important for the light and airy texture of this cake! You can make a homemade version! Read "Expert Tips & Tricks" for instructions.
- Unsweetened Cocoa Powder: Unsweetened cocoa powder (and water) are added to the divided batter to create the chocolate portion of the cake. Natural cocoa powder works great!

Step by Step Process
STEP 1: Preheat your oven to 350 degrees Fahrenheit. Heavily spray your 9x5 inch loaf with baking spray before lining the bottom and a portion of the sides with parchment paper.
STEP 2: In a medium bowl, whisk all purpose flour, baking powder, baking soda, and salt together using a wire whisk until combined.


STEP 3: In a large bowl, use a wire whisk to stir vegetable oil, room temperature eggs, vanilla extract, sour cream, and buttermilk together until smooth.
STEP 4: Carefully,
STEP 5: Pour the dry flour mixture into the large bowl of wet ingredients. Carefully and slowly stir until you see the dry ingredients just disappear into the batter to avoid overmixing and creating a dense cake.
STEP 6: Transfer a little less than half of the batter into the medium bowl that previously held your dry ingredients. This does not need to be exact.


STEP 7: Add cocoa powder and hot water to the batter in the medium bowl and stir to create the chocolate batter.
STEP 8: Pour ⅓ of the vanilla cake batter into your prepared pan. Then, alternate between adding large dollops of vanilla and chocolate batter on top of the vanilla batter. Use a knife to swirl creating an "S" motion twice.


STEP 9: Bake the loaf for about 40-45 minutes or until the top of the loaf is golden brown in color, the top springs back when poked in the center with your pointer finger, and a toothpick inserted into the center comes out with moist crumbs.


STEP 10: Prepare the ganache. Heat heavy whipping cream in a small saucepan over medium heat until it just begins to simmer.
STEP 11: Pour the ganache on top of your bowl of chocolate chips. Push the chocolate chips below the heavy whipping cream to ensure all parts of the chocolate are being heated.
STEP 12: Start mixing by making small circles in the center of the bowl. Continue making a swirl motion and slowly begin working outside the center of the bowl as the mixture combines. Let the ganache sit for 10 minutes before pouring it on top of the cake.
How To Make the Marble Swirl
STEP 1: Divide the batter into almost equal portions.
STEP 2: Add cocoa powder and hot water to the bowl with the smaller amount of batter.


STEP 3: Pour ⅓ of the vanilla batter into the loaf tin.
STEP 4: Add a 2-tablespoon dollop of chocolate batter at one of the pan.


STEP 5: Add a 3-tablespoon dollop of vanilla batter directly next to the chocolate dollop.
STEP 6: Repeat this process with the remaining batter.


STEP 7: Use a knife to make an "S"-shaped swirl across the pan twice

Frequently Asked Questions
Swirling both chocolate and vanilla cake batter together results in an effect that resembles the look of marble! Similar to each slab of marble, each pound cake will look a little different since
After baking and allowing the cake to fully cool, you can store the unfrosted cake at room temperature for up to 4 days or in the freezer for up to 4 months. Store the decorated cake at room temperature for up to 2 days due to the ganache, in the fridge for up to 5 days, or in the freezer for up to 4 months.

Expert Tips
Room Temperature Ingredients: Using room temperature ingredients is imperative to creating a light and fluffy cake. In this recipe, you'll need eggs, sour cream, and buttermilk at room temperature. If you forget to leave your ingredients out of the fridge ahead of time-
- Eggs: place eggs in a bowl of hot water for 5 minutes before using
- Sour Cream: heat sour cream in the microwave for 15 seconds before stirring and using
- Buttermilk: heat buttermilk in the microwave for 10-15 seconds before using
Homemade Buttermilk: Buttermilk creates a tender crumb that will not be achieved with regular milk. However, you can make your own buttermilk from scratch by following this method:
- Add 2 teaspoons (10g) of white distilled vinegar or lemon juice to a liquid measuring cup or bowl on a kitchen scale
- Pour room temperature dairy milk until the ⅔ cup mark or 160g is reached
- Stir the mixture together before letting it sit for about 5 minutes
- Milk should thicken and slightly curdle and will then be ready for use
Sour Cream Substitution: If you do not have sour cream, you can use greek yogurt as a substitution.
Related Recipes
Print
Marble Loaf Cake
- Prep Time: 20 minutes
- Cook Time: 40 minutes
- Total Time: 1 hour
- Yield: 9x5 loaf 1x
- Category: Cake, Marble Cake, Loaf Cake
- Method: Bake
- Cuisine: American
Description
This Marble Loaf Cake is moist, easy, and swirls both chocolate and vanilla into one loaf cake! The cake is so light and fluffy thanks to sour cream and oil, is so simple and made with just a handful of ingredients you likely already have in your kitchen, and takes just 20 minutes to prepare.
Ingredients
For the Cake
- 1 ½ cups (210g) all purpose flour, properly measured
- 1 ½ teaspoons baking powder
- ¼ teaspoon baking soda
- ½ teaspoon salt
- ⅔ cup (134g) vegetable oil
- 1 cup (210g) granulated sugar
- 2 large eggs (100g), room temperature
- 1 teaspoon vanilla extract
- ⅓ cup (80g) sour cream, room temperature
- ⅔ cup (160g) buttermilk, room temperature
- 3 tablespoons (15g) unsweetened cocoa powder
- 2 tablespoons (30g) hot water
For the Ganache
- ⅔ cup (120g) semi sweet chocolate chips
- ⅓ cup (80g) heavy whipping cream
Instructions
For the Cake
- Preheat your oven to 350 degrees Fahrenheit. Line a 9×5 inch loaf pan with parchment paper and spray the paper and pan with cooking spray to ensure the cake will come out cleanly after baking and cooling.
- In a medium bowl, whisk all purpose flour, baking powder, baking soda, and salt together with a wire whisk.
- In a large bowl, whisk vegetable oil, granulated sugar, room temperature eggs, vanilla extract, room temperature sour cream, and room temperature buttermilk together with a wire whisk until smooth.
- Carefully, whisk the dry ingredients into the wet ingredients. Only mix until you see the flour pieces disappear into the batter. You should not see any chunks of flour, but do not mix past when the batter is smooth to avoid dense cake.
- Separate the batter into almost equal portions. In the smaller bowl of batter, add the 3 tablespoons of cocoa powder and hot water to create the chocolate cake portion of the marble cake.
- Add about ⅓ of the vanilla batter to your prepared pan.
- Add about a 2-tablespoon-sized dollop of chocolate batter towards the end of one side of the pan. Place a 2-tablespoon-sized dollop of vanilla batter directly next to and slightly on top of the chocolate batter.
- Repeat this process across the pan and until all of the batter is used.
- Use a knife to make an “S” motion twice inside of the loaf pan to create the swirled marble effect.
- Bake the cake for 38-44 minutes or until the top is cracked in the center, the center looks slightly soft, the top is light golden brown in color, and a toothpick inserted into the center comes out with moist crumbs.
- Allow the cake to cool in the pan for at least 30 minutes before removing and topping with ganache.
For the Ganache
- Pour your chocolate chips into a glass bowl.
- In a small saucepan, heat heavy cream over medium heat until the mixture just starts to bubble.
- Pour the heavy cream on top of the chocolate chips. Use a spoon to push the chocolate chips below the heavy cream to ensure all parts of the chocolate are touched by the hot cream.
- Allow the chocolate chips and hot cream to sit for about 2 minutes.
- Using a wire whisk, start mixing by making small circles in the center of the bowl. Continue making a swirl motion and slowly begin working outside the center of the bowl as the mixture combines.
- Let the ganache sit for 10 minutes before topping the cake to firm up.
For Decorating
- Top the cooled loaf cake with the slightly-firmed ganache.
- Use a knife or spoon to spread the ganache on top of the cake and towards the sides.
- Place the loaf cake in the fridge for 30 minutes to firm up before slicing and serving.
- Store the cake at room temperature tightly covered or in an airtight container for up to 2 days before transferring to the fridge for an additional 2 days or in the fridge for up to 5 days.
Notes
Room Temperature Ingredients: Make sure your eggs, sour cream, and buttermilk are at room temperature before using for a fluffy, light cake.
Mixing: Only mix the dry ingredients into the wet until you see the dry ingredients just begin to disappear. Overmixing past this point leads to dense cake.
Ganache: Let the ganache sit in the bowl for 10 minutes before topping on the cake. Refrigerate the frosted cake for 20 minutes before serving for a firmer ganache topping.
Keywords: Marble Cake, Loaf Cake, Marble Loaf Cake, Loaf Tin, Sour Cream Pound Cake, Ganache Cake
Emily L says
I made this loaf cake last night and I love how quick and easy it is to come together! I didn’t make the ganache but the cake has the perfect flavor and is deliciously moist. I’m dreaming about the next slice I’m going to have. Thanks for the great recipe! I’ll definitely be turning back to this one in the future.
★★★★★
Elise says
Yay! Thank you so much for leaving such a sweet review, Emily! It makes me so happy to hear that you enjoyed baking and eating this cake!
Catherine says
One of the easiest and best loaf cakes I’ve made!
★★★★★
Elise says
Thank you, Catherine! I'm so happy you enjoyed this cake!