Use exactly 1/3 cup vegetable oil per box of cake mix—too much creates greasy cookies, too little yields dry, crumbly results. Measure carefully with a liquid measuring cup for consistency.

Use room-temperature eggs for better emulsification and a more tender, cake-like texture. Cold eggs can create a tougher cookie with uneven mixing.

Bake until the edges are just set but the centers still look slightly underdone—they'll continue cooking on the hot pan and develop that signature soft, chewy texture.

Let cookies cool on the baking sheet for 5 minutes before transferring to a wire rack; this allows them to firm up enough to hold their shape while staying impossibly soft inside.

Replace the oil with melted butter for deeper flavor, or add 1 tablespoon of freeze-dried strawberry powder to intensify the fruity taste beyond the cake mix alone.