1. Preheat oven to 350°F and line a 12-cup muffin tin with liners.

2. In a bowl whisk flour, cocoa powder, baking soda, and salt.

3. In another bowl beat butter, granulated sugar, and brown sugar until fluffy.

4. Add eggs one at a time then vanilla and peppermint extracts and mix.

5. Stir in sourdough starter and buttermilk until combined.

6. Alternate adding dry ingredients and hot coffee into wet mixture, mix gently until smooth.

7. Fill liners two thirds full and bake 18 to 20 minutes until a toothpick comes out clean.

8. Cool cupcakes in pan for 5 minutes then transfer to a wire rack.

9. Melt white chocolate until smooth and let cool slightly.

10. Beat softened butter then gradually add powdered sugar.

11. Add melted white chocolate, vanilla, cream, and salt and whip until silky.

12. Frost cooled cupcakes and garnish with crushed peppermint candies.