Preheat the oven to 350°F (175°C) and line a 12-cup muffin pan with paper liners.
In a large mixing bowl, whisk together the flour, granulated sugar, cocoa powder, baking soda, and salt until well combined.
In a separate bowl, mix the almond milk and apple cider vinegar. Let it sit for about 5 minutes to curdle slightly.
Add the vegetable oil, vanilla extract, red food coloring, and white vinegar to the almond milk mixture. Whisk until smooth.
Pour the wet ingredients into the dry ingredients and stir until just combined. Be careful not to overmix; a few lumps are okay.
Divide the batter evenly among the lined muffin cups, filling each about two-thirds full.
Bake for 18-20 minutes or until a toothpick inserted in the center comes out clean.
Allow the cupcakes to cool in the pan for 5 minutes, then transfer them to a wire rack to cool completely.
For the frosting, beat the vegan butter and cream cheese (if using) in a mixing bowl until creamy and smooth.
Gradually add the powdered sugar, mixing until combined. Add the vanilla extract and enough plant-based milk to reach your desired frosting consistency.
Once the cupcakes are fully cooled, frost them generously with the icing, and enjoy your delicious vegan red velvet cupcakes!