Preheat oven to 350 degrees F. Grease and lightly flour a 10-inch fluted tube pan; set aside. Set aside 1/2 cup of the flour. In a large bowl, combine the remaining 2 cups cake flour or 1-3/4 cups all-purpose flour, the baking powder, baking soda and salt.

In another large bowl, whisk together buttermilk, granulated sugar, oil, eggs and vanilla. Add buttermilk mixture to flour mixture. Beat mixture with a wire whisk just until combined. In a medium bowl, combine cocoa powder and espresso powder. Add half of the buttermilk mixture (about 1-3/4 cups), stirring until smooth; set aside. Add the reserved 1/2 cup flour to the remaining buttermilk mixture, whisking just until combined.

Spoon half of the white batter evenly into the prepared pan. Carefully spoon half of the chocolate batter atop the white batter in pan in an even layer. Repeat layers with remaining batter.

Bake for 30 to 35 minutes or until a toothpick inserted near center comes out clean. Cool in pan on a wire rack for 15 minutes. Remove cake from pan. Place cake on a wire rack set over a sheet of parchment or waxed paper. Using a long wooden skewer, poke cake in several places, poking all the way through to bottom of cake.

In a small bowl stir together 1 1/4 cups powdered sugar and 1 teaspoon light-color corn syrup. Stir in 1 to 2 tablespoons cooled brewed espresso or strong coffee to reach drizzling consistency.

Slowly pour Coffee Drizzle evenly over top of cake. Cool completely. Sprinkle with powdered sugar and/or cocoa powder.