If you have milk and butter in your fridge, you have all the ingredients necessary to turn a box of mac and cheese into dinner. But there are some nights where you're probably craving something that's slightly more refined than the classic stovetop fare of your childhood. When that's the case, Lifehacker has a tip for upgrading your boxed macaroni and cheese without adding any time to the recipe.

To bring your mac to the next level, swap the regular milk that's recommended on the box for the same amount of buttermilk. Unlike whole milk, buttermilk is cultured. This gives it a sour flavor that can add tanginess to everything from biscuits to Thanksgiving turkey.

In mac and cheese, this ingredient adds nuance to a dish which mostly tastes like salt and fat. Buttermilk is a source of acid, which is essential for balancing out fatty foods. And to maintain that creamy richness you still expect from mac and cheese, make sure you mix real, full-fat butter into the pasta with the buttermilk.

Using cultured dairy is a quick way to elevate boxed mac and cheese, but if you're willing to put a little more effort into your meal, a whole world of tasty possibilities opens up. Here are some creative mac and cheese recipes we recommend. (Plus a version that's been hailed as "the world's best" that is incredibly easy to make.)

[h/t Lifehacker]