Grease and flour a 6 inch cake pan. Line bottom with wax paper or parchment paper.
Blend together butter and sugar.
In another bowl combine flour, cocoa powder and salt.
In another bowl combine egg, buttermilk, vanilla, vinegar and baking soda.
Alternately add the flour mixture and the buttermilk mixture into the sugar mixture.
Add in red food coloring.
Pour batter into prepared cake pan and bake for 20-25 minutes or until a toothpick comes out clean.
Cool for 10 minutes and then remove cake from pan onto a baking rack and cool completely before frosting.
Cream Cheese Frosting
Stir together cream cheese and butter until smooth.
Add in powdered sugar and salt.
Add in vanilla.
Frost cooled cake. Refrigerate until ready to serve.
Video
Notes
I prefer to mix small batch cakes together by hand instead of in a stand mixer or using an hand electric mixer. You have less of a tendency to over mix the batter that way. Over mixing will cause the cake to be tough and not tender.
Be sure and use room temperature cream cheese in your frosting so you don't end up with lumps.
Use room temperature eggs, butter and milk for best results. Room temperature ingredients incorporate easier and faster and keep the cake more tender
This cake can serve 2-4 people depending on how you slice the cake.