Preheat the oven to 350° F (176° C). Line mini cupcake tins with cupcake liners and spray the liners with a little spray oil.
In a medium mixing bowl add 1 cup of plant-based milk and 1 teaspoon of apple cider vinegar and let it sit for about 5 minutes until the milk curdles.
Then add 3/4 cup of sugar, 1/3 cup oil, and 1 tablespoon of vanilla, then stir with a whisk until the sugar dissolves.
Add 1 1/4 cups of flour, 2 tablespoons of cornstarch, 3/4 tsp baking powder, 1/2 tsp baking soda, and 1/4 tsp salt.
Stir again for 30 -45 seconds until you have a smooth batter, but don't overmix. (Then if you are making funfetti cupcakes, gently fold in 1/3 cup vegan sprinkles just before filling your cupcake liners.)
Fill your prepared liners 3/4 of the way full with cake batter. (This will be about 2 tablespoons of batter in each one. I find that a cookie scoop is a perfect tool to get the exact amount needed for each cupcake.)
Bake the cupcakes at 350° F (176° C) for 15 minutes.
Allow them to cool completely before frosting.
Notes
Be sure to spray the cupcake liners with some spray oil before baking, so they don't stick to the paper.
Fill the mini cupcake liners 3/4 of the way to the top of the liner. You only need a small amount (a little less than 2 tablespoons) of cupcake batter. You don't want it to overflow and bubble over.
If you forget to spray the liners before filling them with batter, they may stick to the liner especially when warm, but after they sit for an hour or two they will come out of the liners without sticking.