Allow vegan butter and canned coconut milk to reach room temperature before mixing to ensure a smooth, creamy batter and prevent lumps that can create dense cupcakes.

Mix apple cider vinegar with the coconut milk first and let sit for 1-2 minutes to create a vegan buttermilk, which reacts with baking soda for optimal lift and tender crumb.

Whip vegan butter for 2-3 minutes until pale and fluffy before adding powdered sugar, then alternate additions of sugar with small amounts of plant milk to achieve a spreadable, not-greasy frosting.

Don't overmix the batter once you add flour; fold it in gently with a spatula to avoid developing gluten, which creates a tough, dense cake instead of a fluffy crumb.

Cool cupcakes completely on a wire rack for at least 30 minutes before frosting; warm cakes will melt the vegan buttercream and cause it to slide off or become greasy.