19 ways to make grilled cheese sandwiches even better using things you have in your kitchen

"You don't want to choose a bread that's super dense or something that's not going to get crisp," Laura Werlin told Insider. "Sourdough is my go-to bread for grilled cheese sandwiches. It's the most versatile and keeps it interesting. Texturally, it's got all these little nooks and crannies that allow the butter, oil, or mayonnaise to really crisp up."

"You want to get the ratio of bread to cheese right, and you're not going to get that if your bread is too thick," she continued. "A half-inch slice of bread is what I recommend."

"What you want to be careful of is choosing a bread that has sugar in it," Heidi Gibson said. "If your bread has sugar in it, it will burn more quickly. You're going to be better off with a more rustic bread than a loaf of processed sandwich bread."

"Grated cheese often works better than sliced cheese," Werlin said. "That's because you want the cheese to melt as quickly as possible, so the bread doesn't have a chance to burn. There's nothing more disappointing than making a grilled cheese sandwich and cutting it open to find the cheese isn't oozing out because it's not cooked through."

Werlin also explains that you can mix butter with some grated Parmesan and brush it on the outside to get a crispy coating.

Werlin recommends using cheeses that are "medium to medium-hard," such as Monterey Jack, Swiss, or Gruyere. Heidi Gibson also recommends a cheese like Havarti, which is a little softer and melts very easily.

You can also experiment with cheeses that have a distinct flavor, such as goat cheese, blue cheese, or ricotta. However, you want to be sure that none of the other ingredients compete or distract with the flavor of the cheese you choose.

"The cheese or cheeses that you use will determine the ooze factor," Werlin said. "There's nothing better than melted brie, but if you use just that on a grilled cheese sandwich it doesn't become a stretchy cheese, it just becomes kind of messy. If you want the stretchy factor, you're going to want to add a slightly harder cheese to get that stretch factor."

Mayonnaise can add another savory flavor element to a grilled cheese sandwich, so you just want to be wary if you're using other strongly flavored ingredients.

"Mayonnaise definitely makes for a crisp sandwich, there's no question," Laura Werlin said.

Both Laura Werlin and Heidi Gibson swear by using butter on the outside of grilled cheese sandwiches.

"I just love butter so much and the richness it brings to a sandwich," Werlin said. "What's on the inside will really dictate what fat I'm using. For example, if I'm making a riff on an Italian Caprese sandwich with tomato and basil, I'm not going to use butter. I'm going to use olive oil."

"You can also make a compound butter by softening the butter and mixing in whichever spices you want to use," Gibson said. "You can add chipotle powder, garlic, sage, rosemary, or thyme and get even more flavor in there. When you spread it on the outside, you get those layers of flavor."

You can elevate the flavor of your grilled cheese by smearing the outside of your bread with everything from olive oil to truffle oil.

Werlin recommends always spreading or brushing the oil directly onto the bread, rather than in the pan, so that the bread gets evenly crispy.

Whether you're using oil, butter, or mayonnaise, Werlin also recommends using a nonstick pan for cooking your grilled cheese sandwich and covering it to expedite the melting of the cheese.

Many people might have jams floating around in their pantries without knowing how to utilize them. To add a ton of flavor to a simple grilled cheese, adding ingredients like chutney, pepper jelly, tomato jam, or bacon jam can totally change the flavor profile.

"Any jam, any chutney, even dijon mustard, almost any condiment will lend itself to a grilled cheese sandwich," Werlin said.

"If you've got sweet or savory condiments like pepper jelly or onion relish sitting in the back of your fridge, those work great in a grilled cheese," Gibson said.

In her book "Grilled Cheese, Please," Laura Werlin gives a recipe for a grilled cheese sandwich with whole wheat bread, peanut butter, bologna slices, cheese, and dill pickles. Though this might sound disgusting, she explains that, somehow, the flavors all come together.

"I cook those bologna slices a little bit to get them crispy and put a little mayonnaise on the outside," she told Insider. "It sounds weird, but it's honestly really good."

Bacon is an ingredient that might already be in your fridge or on your weekly grocery list, and adding it to a grilled cheese sandwich can take your meal to the next level.

Read more: The best grilled cheese in every state

Ham pairs perfectly with easily melted cheeses like Swiss or Gorgonzola and adds a ton of flavor without any extra prep work. Simply add a slice or two or your favorite sandwich ham and you're good to go.

"Ham is great, but it should be thinly sliced," Werlin said. "You're adding that smokey flavor."

Cured meats like pancetta or bacon last longer in your fridge than fresh meats and make a great addition to most grilled cheese sandwich combinations.

"I do like pancetta on grilled cheese sandwiches," Werlin said. "The only caveat is that, like bacon, you're going to have to cook it first."

A grilled cheese made with rich, gooey cheese and heavy bread can easily become too rich. Adding leafy greens and other vegetables can cut through that richness and make your sandwich more balanced.

"Arugula and spinach will melt brilliantly," Werlin said. "Almost any vegetable will lend itself to a grilled cheese sandwich, but if it's a hard vegetable like a carrot or broccoli or cauliflower, but they have to be briefly cooked first."

Avocado adds a delicious creamy aspect to grilled cheeses, but you might want to choose a harder cheese with a slightly higher melting point so it doesn't make your sandwich too moist.

Bell peppers can be used in a number of different recipes, so they'll never go to waste in your fridge. However, if you're using them in a grilled cheese sandwich, Laura Werlin recommends cooking them a little bit before adding them.

"Bell peppers should be a little bit softer when you put them in, so you might want to roast them," she said.

"The key with vegetables is getting the water out, otherwise you end up with a watery grilled cheese," Heidi Gibson told Insider.

Heidi Gibson explains that part of the magic of making a gourmet grilled cheese is taking the flavor combinations you love and figuring out how to incorporate them into a grilled cheese sandwich.

"If you look at Italian dishes like butternut squash and sage ravioli, you can make that into a grilled cheese," she told Insider. "It's reformatting those beloved flavors. Butternut squash, Fontina cheese, and sage are great in a grilled cheese. You can make sage butter, roast slices of butternut squash, play with it, and voilà, you've got a really interesting grilled cheese."

Laura Werlin and Heidi Gibson that adding pickled red onions is one way to easily elevate your grilled cheese sandwiches without a ton of effort.

"It takes five minutes to make pickled red onions and they work so well," Gibson said.

"Pickled items are really delicious, particularly when you're using Alpine-style cheeses like Gruyere or Raclette," Werlin told Insider.

"Olives and pickled okra also work really well in a grilled cheese," Gibson said. "Any time of pickle with a hard acid really balances out the cheese."

Cheese and tomato are a match made in heaven, so why not add this common ingredient to grilled cheese?

Werlin also explains that tomatoes are a great addition because you don't have to pre-cook them before adding them to a grilled cheese sandwich.

Read more: I tried 3 canned tomato soups and Campbell's Well Yes! tomato bisque went perfectly with my grilled cheese

"You can take Indian dishes like butter chicken or chicken tagine you might have prepared the night before and put that inside a grilled cheese," Heidi Gibson told Insider. "It's delicious."

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