Preheat your oven to 350 degrees.
Mix the plant milk and apple cider vinegar together and allow to sit for 5 minutes. Then, mix the flour, baking powder, baking soda and salt in a bowl.
In a separate bowl, mix the sugar and oil, then stir in the plant milk and apple cider vinegar mixture, the flax egg, and the vanilla.
Add the dry ingredients and mix until there are no dry bits left.
Take 1 cup of the batter and place it in another bowl and stir in the cocoa and an extra tablespoon or two of plant milk as needed, the batter will be thick.
Line a muffin tray with muffin wrappers, and using a spoon or a cookie scoop with a release trigger, add in 1 tablespoon of each batter, alternating in between to get a layered effect.
Once wrappers are ¾ full, take a toothpick and swirl the colors together a bit, but not too much or you won't be able to taste the different flavors.
Bake for 20-23 minutes, or until a toothpick inserted into the middle of the cupcakes comes out clean.
Allow cupcakes to fully cool before frosting. While you wait for them to cool, add your frosting ingredients to a bowl except the powdered sugar and mix with an electric mixer or vigorously by hand.
