Preheat the oven to 350°F (180°C) and fill the cupcake pan with 24 cupcake liners. Sift together in a bowl the flour, corn starch, salt and cocoa powder.
In a different big bowl, cream together the butter, oil and sugar using a mixer. Beat for about 3 minutesuntil the mixture lightens in color and turns fluffy.
Add in the eggs one by one, then the vanilla and the red coloring as needed.
Add the flour mixture in three additions, alternating with the buttermilk and the coffee, begining and finishing with the flour. Mix for one minute until integrated.
Apart, in a small bowl, mix the vinegar and the baking soda and add it to the main batter fast.
Perfectly beat until the batter is soft, and then pour it in the cupcake liners 3/4 full each.
Bake at 350°F (180°C) for 25 min. or until a wooden stick comes out clean when inserted (it is important however not to open the oven in the first 18 min, of baking).
Once ready take out of the oven and let the cupcakes cool down completely before decorating.
For the cream cheese frosting:
In a big bowl, beat together the butter and cream cheese for 3 minutes until you get a soft consistency.
Beat in, little by little the confectioners sugar, previously sifted, and beat for 4 more minutes until the mixture turns fluffy.
Beat in the vanilla, salt and milk and mix until it is all well incorporated.
Decorate the cupcakes with the frosting. Place the frosting in a pastry pipping bag with a star tip and decorate the cupcakes the way you prefer, or you can simply do this using a spoon.