Cream butter and sugars for about 3 minutes, or till very light and fluffy. Beat in the egg and vanilla.

Whisk together the buttermilk and sour cream and set aside.

Sift together the flour, cocoa, soda, and salt. Add the buttermilk mixture alternately with the dry ingredients, about a third at a time. Mix well.

Spoon batter into paper lined or very well greased muffin pans. Bake in a preheated 350° oven for about 18 minutes, or until a toothpick comes out clean. Cool completely.

Filling: Melt kisses, chocolate chips, and cream in a small glass bowl in the microwave at 50% power, stirring every 30 seconds until smooth.

Let cool for 5-10 minutes, then stir in powdered sugar and peppermint extract to your liking.

Fill the cupcakes either by piping the filling in the middle, or by cutting an inverted cone in the top, pulling it out, spooning in some filling, and replacing the cone. Frost with mint frosting and garnish with a halved mint truffle kiss.

Frosting: Beat together cream cheese and butter till smooth. Add remaining ingredients, adding enough cream to achieve the correct consistency. Pipe onto the top of cupcakes using a large star tip. (For best piping, the frosting needs to be pretty stiff.)