Preheat the Oven and Prepare the Pan:
Preheat the oven to 350°F (177°C).
Line a baking sheet with parchment paper or a Silpat mat.
Make the Cookie Dough:
In a large mixing bowl, combine the cake mix, eggs, and oil. Stir until the dough is smooth.
If you’re adding mix-ins like chocolate chips, M&Ms, or chopped nuts, fold them in now.
Scoop the Dough:
Using a cookie scoop or tablespoon, scoop the dough onto the prepared baking sheet, placing the dough about 2 inches apart.
Bake the Cookies:
Bake for 8-10 minutes, or until the edges are slightly golden.
Once baked, allow the cookies to cool on the baking sheet for about 4 minutes before transferring to a wire rack to cool completely.
Optional Frosting:
If you want to frost your cookies, beat the softened butter until creamy.
Gradually add the powdered sugar and mix until smooth. Add milk and vanilla extract, and beat until you achieve the desired frosting consistency.
Frost the cooled cookies and add sprinkles or extra mix-ins as garnish.