For the cupcake batter: Preheat the oven to 350 degrees F. Line cupcake pans with cupcake liners (for a total of 24 cupcakes); lightly spray the liners with cooking spray.
In a medium mixing bowl, sift together the cake flour, baking powder, baking soda and salt and set aside. In the bowl of a stand mixer with a paddle attachment, cream the butter and sugar. Add the bananas and beat until smooth. Mix the vanilla extract and eggs into the banana mixture, scrape down the sides of the bowl and beat until incorporated, about 1 minute. Add the dry ingredients and buttermilk to the banana mixture in three parts, alternating between the dry and wet ingredients. Scrape down the sides of the bowl and beat for 30 seconds between each addition.
Scoop one scoop of the batter into each cupcake liner. Bake until the cupcakes bounce back from gentle pressure, about 20 minutes. Remove from the pans and cool.
For the white chocolate ganache: In a microwave-safe bowl, microwave the heavy cream, anise and cardamom in 30-second intervals until hot but not boiling. Add the white chocolate and stir gently using a rubber spatula until the chocolate is melted and the mixture is smooth.
To assemble, dip the cooled cupcakes in the melted white chocolate ganache. (For a thicker frosting, cool the ganache and beat with a hand mixer until light and fluffy. Using a pastry bag fitted with an open tip, frost the cupcakes with the beaten ganache.)
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.