Cookies and milk are the perfect anytime snack. We love them, Santa loves them and they’re a nifty homemade gift when the dollar bills are running low. But perfecting the cookie is an absolute mare. How come we never get them just like the M&S ones? Luckily food blogger Tessa Arias from Handle The Heat has conducted multiple controlled experiments to finally understand and perfect the art of the cookie. Tessa has a culinary degree and over six years in the food industry. She’s written a cookbook and an ebook and basically really knows her shit. We trust her. In a recent post on her blog, Tessa tested various ingredients and techniques that can affect the taste, texture, and appearance of chocolate chip cookies. She altered the use of baking powder, sugars, flours and butter to determine what the perfect method is. And it turns out the secret is unbelievably simple. The trick? Chill your dough for 24 hours before use. Tessa writes: “This produced cookies that were slightly thicker, chewier, darker, and with a better depth of butterscotch flavor. If you have time, try chilling your next cookie dough for at least 24 hours, or up to 48 hours”. Now we know.