Step 1

Bring cola and sugar to a boil in a medium saucepan over medium-high. Boil, uncovered, stirring occasionally, until reduced to 1 cup, 30 to 40 minutes. Remove from heat. Stir in lemon juice. Reserve 1/4 cup cola syrup in a liquid measuring cup for glaze.

Step 2

Preheat oven to 350°F. Coat a 12-cup Bundt pan with baking spray. Stir butter, brown sugar, and granulated sugar into remaining 3/4 cup cola syrup in saucepan. Cook over medium-low, stirring often, until butter is melted and sugars are dissolved, about 3 minutes. Remove from heat. Let cool 5 minutes.

Step 3

Whisk together flour, cocoa, espresso powder, salt, baking soda, cinnamon, baking powder, nutmeg, and cloves in a large bowl. Whisk together eggs and egg yolks, buttermilk, sour cream, vanilla, and zests in a medium bowl; gradually whisk in slightly cooled syrup mixture until well combined. Make a well in center of flour mixture; add egg mixture, stirring until well combined. Spoon batter into prepared Bundt pan. Bake in preheated oven until a wooden pick inserted in center of cake comes out clean, 40 to 45 minutes. Let cake cool in pan on a wire rack 15 minutes. Invert cake onto wire rack, and let cool completely, about 1 hour and 30 minutes.

Step 4

Whisk together powdered sugar, melted butter, cocoa, and reserved 1/4 cup cola syrup in a medium bowl until smooth. Whisk in milk until creamy, pourable, and smooth.

Step 5

Place cake on a plate. Pour glaze over cake. Let stand at room temperature 10 minutes. Serve with whipped cream and cherries, if desired.