Patty Saveurs

Make the cupcakes:

Preheat your oven to 350°F (175°C) and line a muffin pan with cupcake cups

In the bowl of a stand mixer fitted with the paddle attachment, or with a hand mixer, cream butter and sugar together on medium high speed until light and fluffy, about 3-4 minutes

Add sour cream and vanilla extract, mix until incorporated

Add egg whites in two batches, mixing until well combined after each

Into a separate bowl, mix together the flour, cocoa powder, baking powder and salt

Combine milk and water in a small measuring cup

With the mixer on medium/low speed, add half the flour mixture, mix until incorporated, then pour the milk mixture, mix well, lastly pour the other half flour mixture

Finish mixing with a spatula, scraping the sides and checking that there is no more flour at the bottom of the bowl

Fill the liners about halfway and bake for 15-17 minutes, or until a toothpick inserted in the center comes out clean

Let cool a few minutes in the pan, then remove to a cooling rack, let cool completely before frosting

Make the cream cheese frosting:

Make a water bath/bain-Marie, into a saucepan, boil about 2 inches water, put a heatproof bowl on top, add the chocolate and stir until melted, set aside to cool

In the bowl of your stand mixer fitted with the paddle attachment, add the butter and cream cheese, mix to combine

Add the icing sugar in few increments, mixing well after each addition

Lastly add the cooled melted chocolate, check the consistency, if your frosting is a bit too liquid, add more icing sugar 1 tablespoon at a time, conversely if your frosting is too thick, add 1 teaspoon at a time heavy cream or sour cream

Frost cupcakes the way you like best, I used a Wilton 109 tip called Drop Flower Small

Keep in your refrigerator for a few days, do not forget to take the cupcakes out of your fridge about 30 minutes before enjoying so to allow the frosting to come to room temperature