Preheat oven to 350°. Beat butter at medium speed with an electric mixer until creamy. Gradually add sugar; beat until blended. Add eggs and vanilla; beat at low speed until blended.
Stir together cola, buttermilk, and bourbon in a small bowl. Combine flour and next 3 ingredients in another bowl. Add flour mixture to butter mixture alternately with cola mixture, beginning and ending with flour mixture. Beat at low speed just until blended after each addition, stopping to scrape bowl as needed. Pour batter into 3 lightly greased 12-cup Bundt brownie pans, filling each three-fourths full.
Bake at 350° for 12 to 15 minutes or until a wooden pick inserted in center comes out clean. Cool in pan on a wire rack 10 minutes. Remove from pans to wire racks, and cool 30 minutes. Drizzle warm Bourbon-and-Cola Glaze over cakes.
Go Big: Batter can be poured into 1 greased and floured 15-cup Bundt pan. Bake at 350° for 45 to 50 minutes or until a wooden pick inserted in center comes out clean.