Texas Sheet Cake with Watermelon White Chocolate Fudge Frosting
A twist on the classic cocoa sheet cake recipe, this version features a bold hot pink white chocolate fudge frosting flavored with fresh watermelon juice.
Servings 30 slices
Calories 262kcal
Ingredients
Texas Sheet Cake
- 1 Cup Butter
- ¼ Cup Cocoa Powder
- 6 Tbsp Water
- 2 Cups All-purpose flour
- 2 Cups Sugar
- 1 tsp Baking Soda
- 2 Eggs
- ½ Cup Sour Cream
Watermelon White Chocolate Fudge Frosting
- 1 ½ Cup Cubed Watermelon or ½ cup juice
- ½ Cup Unsalted butter room temperature
- ⅔ Cup White Chocolate Chips
- 4 Cups Confectioners Sugar
- Food Coloring optional (I used 1 drop of red)
Instructions
Texas Sheet Cake
- Preheat the oven to 350°F with a rack in the center. Prepare a jellyroll pan (or sheet pan with sides) by lightly coating with cooking spray, lining with a layer of parchment paper, and then greasing the parchment with more spray.
- In a large microwave-safe bowl, combine the butter, cocoa, and water. Heat in the microwave in thirty second increments, stirring after each, until melted.
- In a medium bowl, whisk together the flour, sugar, and baking soda. Add the dry ingredients to the butter mixture and stir to fully combine. Add in the eggs and sour cream, and mix well.
- Transfer the batter to the prepared pan, and spread into the corners of the pan by tilting and using a silicone spatula. Bake for 23-28 minutes, until the center is springy and a toothpick comes out clean.
- Let the cake cool in the pan for at least 10 minutes. Then carefully use the parchment paper to slide it onto a surface. If you prefer, you can leave the cake in the pan until after it is frosted then fully cooled.
Watermelon White Chocolate Fudge Frosting
- While the cake is baking, prepare the frosting. Muddle or blend the watermelon, and then push it through a fine mesh strainer until you have ½ cup of juice. Reduce watermelon juice to ⅓ cup
- Add the juice to a small saute pan, and heat over medium until bubbling. Allow the juice to reduce to ⅓ of a cup, about 5 minutes. Note: Check the amount by transferring the reduced juice back into a measuring cup. If it needs more time, add it back to the pan and continue.
- In a small microwave safe bowl, add the white chocolate chips. Melt these in the microwave in 30 second increments, stirring after each until smooth. Add the reduced watermelon juice to the melted white chocolate, and stir to thoroughly combine.
- Add the butter to a bowl of a stand mixer fitted with the paddle attachment. Mix on medium-low until light and fluffy, about two minutes.
- Add in the sugar in ½ cup batches, each with a small splash of the watermelon-white chocolate mixture. Mix to thoroughly incorporate each batch. With last of the sugar, add in the rest of the watermelon-white chocolate as well. If desired, add food coloring at this point.
- Add the fudge frosting onto the warm cake and spread to coat it completely. It's okay if some runs down the sides. Let the cake and frosting cool fully before cutting and serving. You can chill this in the fridge to cool it faster.
Notes
- Make ahead tip: Store the frosted cake, sliced or unsliced, covered in the fridge for 3-4 days. Freeze tightly wrapped for up to 3 months. Thaw in the fridge overnight before serving.
- If you don't have fresh watermelon you can use watermelon juice instead.
- Without any food coloring the frosting will be an orangey-salmon color, depending on the color of your watermelon. If you'd like it pinker, add red coloring until it's the shade you desire.