Preheat the oven to 350°F
Line a baking sheet with parchment paper
In a bowl, combine 1 box brownie mix, 2 eggs, 1/2 cup oil, and 1/4 cup flour
Mix until a thick dough forms
Add chocolate chips or nuts if desired
Scoop tablespoon-sized portions onto the baking sheet
Leave space between each portion
Bake for 8 to 12 minutes
Let the cookies cool on the baking sheet for 5 minutes
Transfer to a wire rack to cool completely