Preheat your oven to 350 degrees Fahrenheit. While it heats (about 5 minutes), lightly grease two cookie sheets with butter or cooking spray. This prevents sticking and helps cookies bake evenly.

In a large mixing bowl, pour one 18-ounce package of lemon cake mix. Make sure the Cool Whip is thawed (let it sit on the counter for 10-15 minutes if frozen). Add two cups of thawed Cool Whip to the bowl.

Crack one large egg into the bowl with the cake mix and Cool Whip. Using a sturdy spoon or hand mixer, stir everything together for about 2-3 minutes until the mixture is smooth and well combined with no dry cake mix visible. Checkpoint: You are ready to move on when the dough looks uniform and creamy, with no lumps or dry streaks.

Place ½ cup of powdered sugar in a small shallow bowl. Scoop the dough using a teaspoon and drop one ball at a time into the powdered sugar (you'll make about 24 cookies).

Roll the dough ball gently in the powdered sugar until it's completely coated on all sides. The coating should look white and snowy. Place the coated ball onto your prepared cookie sheet.

Space each cookie 1½ inches apart on the sheet. This gives them room to puff up and spread slightly without touching each other.

Place the cookie sheet in the center rack of your preheated 350-degree oven. Set a timer for 10-15 minutes.

Bake until the cookies are light golden brown on the edges and just set in the center (about 10-15 minutes). They should still look slightly soft and pillowy, not dark brown. Checkpoint: You are ready to move on when the edges are light gold and a gentle touch leaves no fingerprint.

Remove the cookie sheet from the oven using oven mitts. Let cookies cool on the baking sheet for 2-3 minutes, then carefully transfer them to a wire cooling rack using a thin spatula.

Allow cookies to cool completely on the rack (about 10-15 minutes) before serving. As they cool, they will firm up slightly.

If the dough is too wet and won't hold its shape, refrigerate it for 15-20 minutes before rolling in powdered sugar.

If cookies spread too much or brown too quickly, your oven may run hot—lower the temperature by 25 degrees next time.

If cookies turn out cakey rather than fluffy, make sure you're using thawed Cool Whip, not whipped cream from a can.

If the powdered sugar coating cracks or falls off, make sure your dough isn't too warm and handle the balls gently.

If cookies are dense or heavy, avoid overmixing the dough—stir just until combined.