Preheat your oven to 350 degrees F and grease two 6" round cake pans. Grab yourself three bowls (one small, one medium, and one large).
In the medium bowl, whisk together the flour, baking soda, baking powder, cocoa powder, and salt. Set this aside for now.
In the smaller bowl, whisk together the buttermilk, food coloring, and vinegar.
Then, in the large bowl, whisk together the beat the oil, sugar, egg, and vanilla together until creamy and smooth.
Then, to this bowl with the oil and sugar, whisk in half of the flour mixture, followed by all of the buttermilk, the hot water, and then the remaining flour. Whisk until the flour is just combined.
Divide the batter evenly between the two cake pans. Use a measuring cup to help portion it out. Bake for 24-26 minutes, or until the cakes are set and a toothpick comes out clean.
Remove the cakes and let them cool completely in the pans. Once cooled, run a knife along the edges to help release the cakes, and then turn them out onto a wire rack. Wrap each layer in plastic wrap, and then place them into the freezer to chill while you prepare the frosting.
To make the frosting, start by beating the butter and cream cheese together in the bowl of an electric mixer fitted with the paddle attachment. Then, add the remaining ingredients and continue beating on medium-high speed until fluffy, around 3-4 minutes.