1. Preheat oven to 350° F. Line a muffin pan with 12 cupcake liners. Take the vegan butter out of the fridge and set aside to soften on the counter.
2. Pour the almond milk into a small bowl. Mix in the apple cider vinegar and set aside to curdle.
3. In a medium-sized bowl, sift together the flour, cornstarch, baking powder, baking soda, and salt. Set aside.
4. In the bowl with the almond milk mixture, add oil, sugar, and vanilla and beat until smooth.
5. Slowly beat the flour mixture into the bowl with the wet ingredients until no large lumps remain.
6. Fill each muffin cup two-thirds full and bake for 20 to 22 minutes, or until a toothpick inserted comes out clean.
7. While the cupcakes are baking, make the frosting. Add softened (not melted!) vegan butter to a large mixing bowl and use an electric hand mixer to cream the butter until light and fluffy, about one minute. Add vanilla and mix once more to combine. Add sifted powdered sugar in half-cup measurements and continue mixing until well combined and fluffy, scraping down the sides of the bowl as needed. If the frosting is too thick, add one tablespoon at a time of non-dairy milk until the desired consistency is achieved.
8. Transfer the cooked cupcakes to a cooling rack and allow to cool completely before frosting.
9. Now it's the fun part! Decorate however you choose. These are just some ideas:

   Spiderwebs: Melt 1/3 cup dairy-free chocolate chips with 1/4 teaspoon coconut oil. Add the mixture to a freezer-safe plastic baggie, snip off a small part of the corner and pipe four circles on top of the frosting. Use a toothpick to drag eight lines from the center to the edge to create a web design. Expert tip: do this immediately after piping on the chocolate because it won't work if the chocolate dries.

   Spiders: Open a chocolate sandwich cookie and place one side on top of the frosting. Use melted chocolate to draw legs and to glue on the candy eyes.

   Mummy: Use two dabs of frosting to attach the candy eyes to an unfrosted cupcake. Use a flat tip to pipe on the mummy's fabric strips all over the top of the cupcake around the eyes.

   Monster: Mix the powdered freeze-dried strawberries into the remainder of the frosting. Use a star or flower tip to decorate the cupcake. Attach one big candy eye and use the leftover melted chocolate to pipe on a mouth.

Here's the nutritional info from verywell [1] for one cupcake: