For the cheesecake filling

1. Combine all ingredients and transfer to a piping bag until ready to use.

For the cupcakes

1. Preheat oven to 350 degrees F. Line a standard muffin/cupcake pan with liners.
2. On medium-high speed, cream the butter and sugar until light and fluffy, about 3 minutes. Turn the mixer to high and add the egg. Scrape down the bowl and beat until well incorporated.
3. In a separate small bowl, mix together the cocoa powder, vanilla extract and red food coloring to make a thick paste. Add to the batter and mix on medium speed until completely combined. You may need to stop the mixer to scrape the bottom of the bowl, making sure that all the batter gets color.
4. Reduce the mixer speed to low and slowly add half of the buttermilk. Add half of the flour and mix until combined. Scrape the bowl and repeat the process with the remaining milk and flour. Beat on high until smooth.
5. Again, reduce the mixer speed to low and add the salt, baking soda and vinegar. Turn to high and beat for another couple of minutes until completely combined and smooth.
6. Divide the batter evenly between the cupcake liners and fill with cheesecake filling, about 3 tbsp or so per cupcake. Bake on the middle oven-rack for about 18-20 minutes, or until a thin knife or skewer inserted into the center of the largest cupcake comes out clean. I baked mine for 18 minutes.
7. Cool for 2 minutes and then remove cupcakes from the pan and place them on a cooling rack to cool completely before frosting.

For the frosting

1. In a food processor, pulse the softened butter and cream cheese together until combined.
2. Add 1 cup of the sugar and pulse. Repeat until all the sugar is used.
3. While pulsing, drizzle in the vanilla extract and salt.
4. Frost your cupcakes.
5. ** If you don’t have a food processor, you could use a traditional stand mixer, electric hand mixer, a plain ol’ wire whisk (a sturdy one), or a fork or spoon. Just expect to put more muscle into it if mixing by hand, and note that it will take a bit longer to blend everything together smoothly.