Add the oil, milk, eggs, and vanilla. Stir to just until no large lumps remain.
½ cup vegetable oil, ½ cup milk, 2 large eggs, 1 teaspoon pure vanilla extract
Fill each cupcake tin ¾ full with batter - I use a ¼ cup cookie scoop to ensure they’re all the same size.
Bake for 18-20 minutes or until a toothpick inserted into the center comes out clean.
Transfer the cupcakes to a wire rack and let them cool to room temperature before frosting.
For the Frosting
While the cupcakes cool, make the frosting. Use a stand or hand mixer to beat the butter on medium speed until smooth and creamy, about 2 minutes.
½ cup unsalted butter
With the mixer running on low speed, add the powdered sugar. Increase to high speed and beat until the frosting is light and fluffy, about 2 minutes.
2 cups powdered sugar
Gently fold in the cookie butter.
¼ cup cookie butter
Transfer the frosting to a piping bag fitted with a piping tip and frost the cupcakes as desired.
Notes
Be sure your ingredients are at room temperature, so they mix well.
Make sure you mix your cupcake batter until they are just combined. Don't over or under mix.
Use a cookie scoop to portion out the batter evenly into the cupcake tins.
For a fun decoration, microwave a bit of cookie butter in a microwave-safe bowl until it reaches a runny consistency, then drizzle over top of the frosted cupcakes.
Storage: Store cupcakes in an airtight container in the refrigerator for up to 3 days. Freeze unfrosted cupcakes in an airtight container for up to 3 months. When ready to serve, bring to room temperature and frost.