The Best Condiment For Grilled Cheese Isn't Ketchup Or Mustard

There are several ingredients needed to bring a grilled cheese together expertly. Once you get the best bread sorted for this classic sandwich, and decide on some cheeses, look to your choice of spread. Ketchup calls to mind the classic tomato soup pairing and mustard adds a lovely tang, but it's a few dollops of Kewpie mayonnaise, a Japanese invention, that is our pick for elevating a grilled cheese sandwich.

Kewpie mayo is loved by top chefs and it's no surprise why. Unlike U.S. mayo, Kewpie mayo is made from egg yolk only, rather than the whole egg, which makes its flavor significantly richer. Think of it like adding the umami of an oozing egg yolk to your sandwich without having to fry an over-easy egg. Absolutely delicious without any extra effort — no wonder eggs and cheese are a tried-and-true pairing! You also get a touch of tang from mustard powder and three kinds of vinegar, which does wonders to cut through the gooey cheese and thick bread and add another flavor to the mix. 

The recipes are different for Japanese and American Kewpie, though: the American version only contains one type of vinegar and sometimes lemon juice and contains yeast extract rather than the monosodium glutamate (MSG) found in the Japanese recipe. MSG is completely safe, despite what longstanding myths about Chinese food would have you believe, and creates a tastier Kewpie. Try to track the Japanese version down if you can. But whichever one you snag, schmear it on the inside of the bread to meld with the melted cheese for the creamiest sandwich you've ever had, or take some European inspiration and dip your sandwich in Kewpie like french fries.

Kewpie mayonnaise is impressive as a dip or a spread but adding some to the exterior of your grilled cheese is also a great trick for making a super crispy grilled cheese. Just spread the bread the outsides of your sandwich with a light layer of Kewpie instead of (or in combination with) butter, and cook as you normally would. You can also spread additional butter on the interior of the sandwich so he Kewpie fries and the buttery flavors soften and mix with the cheese. 

But don't stop there — you can add a bunch of extra ingredients to complement or contrast the flavors of your grilled cheese and kewpie. You can add mushrooms or umami salt, to play into the savory flavors even more, but sweet ingredients make a killer grilled cheese too. Try adding sliced blackberries to your sandwich. They aren't overpoweringly sweet, but they can help balance out the umami flavors of the cheese and mayonnaise and their tartness pairs well with Kewpie's slight tang. They'll also make an interesting textural addition to the grilled sandwich. Generally, Gouda and cheddar work well with Kewpie, but to complement the blackberries you add mozzarella or goat cheese as well. You'll have a sandwich with an ooey-gooey center and a crispy mayo-cooked exterior keeping the bread as crispy as possible.