Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper and set aside.

In a large bowl, stir together 1 (15.25 ounce) box lemon cake mix and 1 teaspoon baking powder until evenly combined.

Add 1/3 cup vegetable oil, 1 tablespoon lemon zest, and 2 large eggs (room temperature) to the dry mixture. Mix with a spatula or electric mixer on low until a thick batter forms, scraping the bowl as needed.

Use a cookie scoop or spoon to drop portions of batter onto the prepared baking sheets, leaving at least 2 inches between each cookie.

Bake for 8–10 minutes, until the edges are set. If you used a large cookie scoop, bake 12–14 minutes until the edges are set. Centers may remain slightly soft.

Remove the baking sheets from the oven and let the cookies cool on the sheets for 2–3 minutes. Transfer cookies to a cooling rack and cool completely.

If desired, dust cooled cookies with powdered sugar before serving.