Preheat your oven to 350°F (175°C). In a large mixing bowl, cream the unsalted butter and granulated sugar together until light and fluffy. Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract. Alternate adding the dry ingredients (flour, baking powder, salt) and the whole milk to the creamed mixture, beginning and ending with the dry ingredients, mixing just until combined.
Remove about one-third of the vanilla batter and transfer it to a separate bowl. Stir in the cocoa powder dissolved in hot water until the batter is evenly chocolatey. Pour the vanilla batter into the greased and floured Bundt pan first, then add dollops of the chocolate batter on top. Using a knife, gently swirl the two batters for a classic marbled effect.
Place the Bundt pan in the oven and bake for 45-50 minutes, or until a toothpick inserted into the center comes out clean. Allow the cake to cool in the pan for 15 minutes before carefully inverting it onto a wire rack to cool completely before slicing.
Notes:
Garnishes
While the marbled cake looks gorgeous on its own, a light dusting of powdered sugar can add a dainty touch that’s simple yet elegant. For a little extra wow factor, drizzle some glossy chocolate ganache or a thin vanilla glaze over the top. Fresh berries or a sprig of mint on the side add a fresh pop of color and flavor that complements the cake’s buttery richness beautifully.
