Ingredients:

  • 2 1/2 cups (300g) all-purpose flour, plus more for dusting the pan
  • 1 teaspoon baking powder
  • 1/2 teaspoon baking soda
  • 1/4 teaspoon salt
  • 1 cup (227g) unsalted butter, softened, plus more for greasing the pan
  • 1 3/4 cups (350g) granulated sugar
  • 2 large eggs
  • 1 teaspoon vanilla extract
  • 1 cup (240ml) buttermilk, room temperature
  • 1/4 cup (25g) unsweetened cocoa powder
  • 2 tablespoons hot water
  • 1 cup (120g) powdered sugar
  • 2-3 tablespoons milk (or lemon juice for a tangy glaze)
  • 1/2 teaspoon vanilla extract (optional)

Instructions:

  1. Preheat oven to 350°F (175°C). Grease and flour the loaf pan.
  2. Whisk together flour, baking powder, baking soda, and salt in a bowl. Set aside.
  3. In a separate bowl, cream together the softened butter and sugar until light and fluffy.
  4. Beat in the eggs one at a time, then stir in the vanilla extract.
  5. Gradually add the dry ingredients to the butter mixture, alternating with the buttermilk, beginning and ending with the dry ingredients. Mix until just combined. Do not overmix.
  6. In a small bowl, combine the cocoa powder and hot water to form a paste. Add approximately half the batter to cocoa paste. Stir until well combined.
  7. Drop spoonfuls of vanilla and chocolate batter alternately into the prepared loaf pan.
  8. Use a toothpick or skewer to gently swirl the batters together, being careful not to overmix.
  9. Bake for 45-55 minutes, or until a toothpick inserted into the center comes out clean.
  10. Let the cake cool in the pan for 10 minutes before transferring to a wire rack to cool completely.
  11. Whisk together powdered sugar, milk (or lemon juice), and vanilla extract until smooth. Drizzle over the cooled cake.