1. Heat oven to 350°F. Grease and flour two 8-inch round baking pans. Set aside.
2.In the bowl of a stand mixer fitted with the whisk attachment or in a large bowl with an electric mixer, combine the sugar, flour, cocoa, baking soda, baking powder and salt. Mix on low until dry ingredients are thoroughly combined.
3.Add eggs, buttermilk, coffee, oil and vanilla. Beat on medium speed for about two minutes; the batter will be thin.
4.Pour batter evenly into prepared pans.
5 Bake in preheated oven for 30 to 40 minutes for round pans, or until wooden toothpick inserted in center comes out clean.
6. Cool 10 minutes; remove from pans to wire racks. Cool completely.
7. Meanwhile, make the cheesecake. Prepare an 8-inch springform pan by lining the bottom with parchment paper. To do this, use prepared parchment rounds or trace the bottom of the pan on parchment paper then cut the circle out. Set aside.
8. Using an electric mixer set at medium-high speed, beat the cream cheese in a large bowl until smooth. Beat in the condensed milk a little at a time, scraping the sides of the bowl, as necessary. Beat in the extracts.Fold in the crushed Oreos.
9.Pour the filling into the prepared pan; smooth the top with a rubber spatula. Cover with plastic wrap, and refrigerate until firm, 2 1/2 to 3 hours.
10. Unclasp sides of pan, and remove cheesecake.
11. Make the buttercream frosting. In a stand mixer with paddle attachment, cream the butter until light and fluffy about 2 to 3 minutes. Add the powdered sugar in 1 cup at at time with the mixer on low. Gradually add in the cocoa powder and mix to combine. Then add the heavy cream and extracts. Mix on low until combined, then turn the mixer to medium-high and mix for 8 minutes until very light and fluffy.
12. To make the ganache measure out your chocolate in a medium sized bowl and set aside. Heat the heavy cream in a saucepan on stovetop on medium high heat until until boil. Pour over the chocolate and let sit for 5 minutes undisturbed. Then whisk until smooth. If not using right away, cover in saran wrap and place in the fridge. When ready to use the ganache will have hardened, so heat on low until smooth or microwave in 30 second intervals until liquid again.
13. To assemble the cake, place one cake round on a cake stand or platter for serving. I like to use a round cardboard cake circle underneath the cake. Remove the cheesecake from pan and place on top of the first cake. You may need to trim the cheesecake if it hangs over the cake. Top with the second cake. Frost with the chocolate buttercream frosting, Pour ganache over and top with additional Mint Oreo cookies.