Begin by preheating the oven to 375. Grease a metal loaf pan with non-stick cooking spray or line it with parchment paper.
In a mixing bowl, mix the mix, butter, sugar, vanilla, baking powder, baking soda, and pinch of salt together. Add the flour and mix until a smooth batter is formed. Divide the batter in half by transferring half of it into a separate mixing bowl.
In one of the batter bowls, mix in cocoa powder and red food coloring until well combined. Add as much coloring as you need to get the cake batter red.
Alternate adding the plain batter and the red batter into the loaf pan to create a marble effect. Bake in the oven for 45-50 minutes or until it is completely cooked through the center.
While the red velvet loaf bakes, use a whisk or ideally an electric hand mixer to mix the vegan cream cheese frosting ingredients. Allow the loaf to cool before frosting, serving, and slicing. Enjoy!