• Preheat oven to 350.
• Cream together the butter and sugar. Add the eggs and mix well. Mix in the sour cream and vanilla.
• In a separate bowl whisk together the flour, cocoa, and baking powder.
• Add ⅓ of the dry ingredients to the wet ingredients. Add half the milk. Repeat, until all the ingredients are incorporated.
• Add to muffin pan lined with cupcake liners sprayed with non-stick cooking spray.
• Bake for 18-22 minutes. Cool completely.

Ganache

• Combine the chocolate chips and cream in a glass bowl. Microwave for 30 seconds. Stir. Microwave for an additional 15 seconds. Stir until the chocolate melts. If needed, you can microwave for additional 15-second increments, stirring after each.
• Cool to room temperature.

Frosting

• Cream butter. Add cocoa powder.
• Add the powdered sugar one cup at a time, alternating with the milk.
• Thin with additional milk, a tablespoon at a time, if needed.

Assembly

• Use a small paring knife or apple corer to remove the center of each cupcake.
• Divide the ganache between the cupcakes.
• Pipe the frosting on top of each cupcakes. Garnish with chocolate sprinkles, if desired.