1(15.25 ounce) box lemon cake mix (I used Betty Crocker)
1/2cupvegetable oil (e.g. canola)
Add the lemon cake mix, oil, and eggs, and any mix-ins to a large mixing bowl. Using an electric hand mixer, mix until well combined.
Chill for 30 minutes. I recommend this step since the dough is sticky and you will also get slightly puffier cookies with chilling, but you don't have to chill them.
Meanwhile, preheat your oven to 350F. Line a baking sheet with parchment paper or a Silpat non-stick mat.
Make 2" balls and place them on the baking sheet at least 2" apart since they do spread. Bake for 11-13 minutes until they're set.
Let the lemon cookies cool for a few minutes on the baking sheet, then transfer them to a cooling rack. Once cooled, store cookies in an airtight container.
I made fairly large cookies (dough was rolled into 2" balls), so if you make them smaller, you can for sure make more than 12 cookies.
You can use the larger-sized boxes of cake mix (18.25 ounces) as well - it'll make about 16 2" cookies (keep everything else in the recipe the same). The batter will be less sticky and the cookies will be more puffy - especially if you chill the dough first.