Preheat oven to 350F. Grease three 8-inch round cake pans, and line the bottoms with parchment paper.
In a large bowl, whisk the flour, baking powder, baking soda and salt.
In another bowl, whisk the boiling water and cocoa powder until smooth.
Beat butter and sugar together on medium speed in a bowl of a standing mixer until light and fluffy. Beat in eggs, one at a time. Beat in buttermilk and vanilla extract.
Reduce the speed to low and beat in 1/3 of the flour mixture, followed by half of the chocolate mixture. Repeat with another 1/3 of the flour mixture and the remaining chocolate mixture. Beat in the remaining flour mixture until just incorporated.
Divide the batter and pour into the prepared pans, smoothing the surface with a spatula. Bake 20 to 25 minutes or until a toothpick inserted into the cake comes out clean.
Place the cakes (in the pans) on a wire rack to cool. Then invert the cakes onto a greased rack. Cool completely.
Strain the syrup from the cherries. Set aside.
Use a pastry brush to brush a light layer of syrup on top of each cake layer. Set aside.
To prepare whipped cream frosting, whisk all the ingredients on low speed until frothy, about 30 seconds. Increase the mixer speed to medium high and continue to whisking until the mixture forms stiff peak, 2 to 3 minutes.
To assemble the cake, place one cake layer on your serving plate and spread with about 1/2 cup of whipped cream. then cover with about 15 pieces of cherries. Place another cake layer on top, followed by 1/2 cup whipped cream and cherries. Place the remaining cake layer on top and press lightly to adhere. Frost the entire cake with the whipped cream.
Gently press the chocolate shavings into the sides of the cake.
Using a large star tip to pipe a decorative border with the frosting on the top edge of the cake. Place cherries on top, and sprinkle some more chocolate.