01 - Preheat oven to 350°F. Grease and line an 8-inch square baking pan.
02 - In a large bowl, whisk together flour, sugar, cocoa powder, baking powder, baking soda, and salt until well combined.
03 - Add buttermilk, oil, egg, and vanilla extract to the dry mixture. Beat until smooth. Pour in hot water and mix until fully incorporated.
04 - Pour batter into prepared pan. Bake for 25-30 minutes or until a toothpick inserted in center comes out clean. Cool completely.
05 - Whip heavy cream with powdered sugar, vanilla, and cream cheese until medium-stiff peaks form. Refrigerate until ready to use.
06 - Break cooled cake into small, even crumbs using hands or a fork.
07 - Fill clean flower pots or dessert cups with alternating layers: cake crumbs, cream filling, more cake crumbs, finishing with chocolate cookie crumbs as soil.
08 - Arrange edible flowers, mint leaves, and herb sprigs on top to create a garden effect.
09 - Refrigerate assembled desserts for at least 30 minutes to set flavors and texture.