Step 1: Prepare the Ingredients

1. Start by preheating your oven to 350°F (175°C) and lining a baking sheet with parchment paper. This will prevent the cookies from sticking and ensure easy cleanup.
2. Gather all your ingredients and set them out. This includes measuring your oil or melted butter, cracking the eggs, and portioning any optional add-ins like chocolate chips or nuts.

Step 2: Mix the Batter

1. In a large mixing bowl, combine the brownie mix and flour. Stir well to distribute the flour evenly through the brownie mix. This step is important, as the flour helps the cookies hold their shape.
2. Add the eggs and vegetable oil (or melted butter) to the dry ingredients. Stir until well combined. The mixture should be thick and slightly sticky.
3. If using, fold in the chocolate chips and nuts until evenly distributed throughout the batter.

Step 3: Form the Cookies

1. Using a cookie scoop or tablespoon, portion out the dough onto the prepared baking sheet. Space the dough balls about 2 inches apart, as they may spread slightly while baking.
2. For more uniform cookies, gently press each dough ball down slightly with the back of a spoon or your fingers.

Step 4: Bake the Cookies

1. Place the baking sheet in the preheated oven and bake for 10–12 minutes. Keep a close eye on the cookies, as brownie mix can brown quickly.
2. The cookies are done when the edges look set but the centers may still appear soft. They will continue to set as they cool.

Step 5: Cool and Serve

1. Remove the cookies from the oven and let them cool on the baking sheet for about 5 minutes. This helps them firm up.
2. Transfer the cookies to a wire rack to cool completely before serving. Enjoy your rich, fudgy brownie mix cookies!