Preheat the oven to 350°F. Line a 9-inch pan with parchment paper.

To make the batter: In the bowl of a stand mixer fitted with the paddle attachment, add the butter, cane sugar, and vanilla extract. Mix on low until combined and there are no chunks of butter. Add the milk, sourdough discard, and sour cream and mix on low until combined.

In a separate bowl, add the pastry flour, all purpose flour, cocoa powder, red dye, baking powder, and sea salt and whisk together. With the mixer on low, slowly add in the flour mixture and mix on low until combined. Scrape down the sides of the bowl and mix again until completely combined. Transfer to the prepared baking pan.

Bake for 35 minutes, or until a toothpick inserted in the center comes out clean. Allow to cool completely in the pan.

To make the frosting: In the bowl of a stand mixer fitted with the paddle attachment, add the butter, cream cheese, powdered sugar, red dye, and vanilla extract. Mix on low until combined and then speed mixer up to high for 1 minute or until light and fluffy. Scrape down the sides of the bowl and mix again until smooth.

To make the coating: Melt all chocolate together using a double boiler, or in 30 second intervals in the microwave, making sure to stir between each interval. (I don’t temper the chocolate for these, as they have to be stored in the fridge because of the cream cheese frosting anyway!)

Remove the balls from the freezer. Using a fork like a spoon, dip the cake balls into the dark chocolate and remove so excess chocolate drips off below. Place back on the parchment paper. Sprinkle each ball with the sprinkles after you place down. Do this now, as the cake balls are cold so the chocolate will harden quickly, so you want to do this after each dip or after every couple at least, so the sprinkles stick.

Dip and coat all the balls and top them with sprinkles. Place back in the freezer until the chocolate is set.

Store in the fridge for up to 7 days.