Preheat the oven to 375°F (190°C). Coat 12 mini silicone fluted Bundt molds (or pans) with nonstick spray, place them on a cookie sheet, and set aside.
In a stand mixer, beat the butter and sugar until fluffy. Add the remaining cake ingredients one at a time, mixing thoroughly after each addition. Use a spatula to scrape down the sides as needed until everything is fully incorporated.
Distribute the batter evenly among the Bundt molds and bake for 20 minutes, or until a toothpick inserted comes out clean. Allow the cakes to cool completely on a wire rack before removing them from the molds.
Using the whisk attachment, mix the heavy whipping cream, powdered sugar, and peppermint extract on medium speed until the mixture thickens but is still slightly runny. Top each cake with the frosting and sprinkle with peppermint candies.
Notes
If you'd like to make a regular 10-inch bundt cake, double the recipe's ingredients and bake it in the oven at 350 degrees F for approximately 40 minutes.