For the Platonic ideal grilled cheese sandwich recipe, you don’t need much. The supplies are simple, the prep time is minimal, and the technique is straightforward. This version—crispy on the outside, gooey in the middle, and deeply comforting, especially when served alongside a steaming bowl of tomato soup—doesn’t try to reinvent the comfort-food classic; it simply guides you toward the ultimate expression of it. That means white sandwich bread, sliced mild yellow cheese, a brush of mayo (yes, mayo!) on the outside, and a flash of butter in the skillet. There’s a time and place for fancy grilled cheese—Dijon, smoked gouda, sliced apple—but when you want a truly classic grilled cheese, this is it.

Tips for a perfect grilled cheese sandwich

• What’s the best bread for grilled cheese?
  For a classic grilled cheese sandwich, white sandwich bread offers the best balance of softness and crispness. Skip whole wheat or sourdough; if you want a slight upgrade, a fresh Pullman loaf works well. Aim for slices about ½” thick (a standard grocery store loaf) for even browning.
• Should you use mayo or butter for grilled cheese?
  Both. Spreading mayo on the outside of the bread helps it brown evenly thanks to its higher smoke point, while melting butter in the skillet adds flavor and encourages crisp, golden edges.
• What cheese melts best for grilled cheese?
  For the gooiest grilled cheese sandwich, opt for yellow American cheese. There is nothing quite like it, and even organic versions don’t melt as smoothly. If you prioritize sharp flavor over texture, choose cheddar cheese. A mild cheddar is best for meltability. Want the best of both worlds? Use both on a single sandwich, using the weight measurement given below.
• What type of pan should I use?
  A small skillet—about 8″—keeps the butter concentrated under the sandwich for even browning. Nonstick or well-seasoned cast iron works best, though carbon steel or stainless steel are also effective with careful heat control.
• Cut the grilled cheese in half diagonally. You can, of course, cut your sandwich however you like, but a diagonal cut makes for an especially delightful grilled cheese experience. It exposes just the right amount of melted cheese while offering inviting corners, just waiting to be dunked and devoured.