Step 1: Preheat the Oven: Preheat the oven to 350F (175C). Line baking sheets with parchment paper or silicone baking mats to prevent sticking.
Step 2: Combine Ingredients: In a large bowl, combine the melted butter and cake mix. Mix until a crumbly mixture forms. Add the eggs, one at a time, mixing well after each addition until a smooth dough forms.
Step 3: Incorporate Mix-ins (Optional): If desired, gently fold in chocolate chips, sprinkles, nuts, or other mix-ins into the cookie dough until evenly distributed.
Step 4: Drop by Spoonfuls: Drop rounded tablespoons of cookie dough onto the prepared baking sheets, leaving about 2 inches between each cookie to allow for spreading.
Step 5: Bake: Bake for 12-15 minutes, or until the edges are golden brown and the centers are set. Baking time may vary depending on the oven and the type of cake mix used.
Step 6: Cool and Enjoy: Remove the baking sheets from the oven and let the cookies cool on the sheets for a few minutes before transferring them to a wire rack to cool completely. Serve and enjoy.
Tips and Substitutions: For chewier cookies, slightly underbake them. For crispier cookies, bake them a minute or two longer. The flavor of the cake mix will determine the overall flavor of the cookies, so choose a flavor that complements the desired mix-ins. Unsalted butter is recommended to control the overall saltiness of the cookies; however, salted butter can be used if preferred. If the dough is too sticky, chilling it in the refrigerator for 15-20 minutes can make it easier to handle.