In a large bowl, whisk together the cake mix, eggs, melted & slightly cooled butter, and vanilla just until well combined.
Gently fold the chocolate chips into the batter until distributed evenly.
Use a medium cookie scoop or a spoon to scoop out the dough and place on the prepared baking sheets about 2 inches apart.
Bake for 9 to 11 minutes, rotating the racks halfway through so the cookies are baked evenly. Allow to cool on the pan for 2 minutes before transferring to a cooling rack.
Notes
Makes 26 to 30 cookies. If you'd like some chocolate chips to stick out like in these photos, add 2-3 extra chocolate chips to the tops of each scoop of cookie before baking.For chewy cookies: bake for 9 to 11 minutes, rotating the pans halfway.For crispy cookies: bake for 11 to 13 minutes, rotating the pans halfwayStorage: Store cookies in an airtight container at room temperature for up to one week. You can also freeze these cookies in a single layer in an airtight, freezer-friendly container, for up to two months.