For National Grilled Cheese Day, Here Are 8 Facts About the Classic Sandwich

Every year, April 12 is dedicated to celebrating one of America's most popular and classic sandwiches -- the grilled cheese.

UberEats

To recognize this national holiday, we've rounded up some out-there facts about the tasty food item. From the world's most expensive grilled cheese to the grilled cheese's place in World War II history, these eight facts might surprise you.

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1. The most "grilled cheese loving" cities are Baltimore, San Diego and Cincinnati, according to UberEATS.

2. UberEATS has also found that the most popular day of the week to order a grilled cheese is Saturday. The least popular day is Tuesday.

3. The most expensive grilled cheese in the world is the $214 "Quintessential Grilled Cheese" from Serendipity 3 in New York City. The sandwich features white truffle butter and rare Caciocavallo Podolico cheese between two pieces of French Pullman bread made with Dom Perignon champagne and 24-karat edible gold flakes.

4. In 1994, a woman named Diana Duyser saw an image of the Virgin Mary on her grilled cheese sandwich after taking a bite, then placed it in a plastic bag. Ten years later, she put it up for sale on eBay. Online casino GoldenPalace.com won the bid and paid $28,000 for the sandwich depicting the mother of God.

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5. Grilled cheese sandwiches were very popular during World War II, and Navy cooks were instructed to prepare "American cheese filling sandwiches" by government-issued cookbooks.

6. The Grilled Cheese Invitational was an annual grilled cheese cook-off that took place in Los Angeles from 2006 to 2014.

7. The actual term "grilled cheese" did not make an appearance until the 1960s. Before then, it was referred to as a "melted cheese" or a "toasted cheese."

8. According to Food & Wine, one of the best grilled cheese sandwiches in the country is from The American Grilled Cheese Kitchen in San Francisco, made by Heidi Gibson, an engineer with degrees from MIT. She was also a winner in the 2011 Grilled Cheese Invitational.