Directions

1. Preheat oven to 350 degrees. Brush inside of each flowerpot with oil, and line bottom with parchment paper round. Brush parchment with oil, and lightly dust with cocoa.
2. Sift cocoa, flour, sugar, baking soda, baking powder, and salt into the bowl of an electric mixer fitted with the paddle attachment. Add egg and yolk, 3/4 cup warm water, buttermilk, oil, and vanilla; mix on low speed until smooth, about 1 minute.
3. Divide batter among prepared pots, filling each about two-thirds full. Transfer to a rimmed baking sheet. Bake, rotating sheet about halfway through, until a cake tester inserted into centers comes out clean, 45 to 50 minutes. Let cakes cool completely in the flowerpots on a wire rack.
4. Frost cakes with an offset spatula; sprinkle with crushed cookies. Top with candies; "plant" 1 mint sprig in each cake.