The Meximelt was a specialty menu item, previously available at Taco Bell.
It was a cross between a Fresco Soft Taco and a quesadilla. It had the flour tortilla, seasoned ground beef, and fiesta salsa of a Fresco Soft Taco but the melted three cheese blend of a quesadilla.
The Meximelt was one of the longest-running menu items at Taco Bell, having been around for nearly 30 years. The trademark was filed May 31, 1988, as a "tortilla for consumption on or off premises". It was also one of few menu items that has not seen any update, with no variants of the Meximelt having ever been released. As of 04/05/2019 the Meximelt is no longer available on the menu. That said, there were some workarounds for ordering, as documented by this video: https://www.youtube.com/watch?v=1htOkyq3s8s
The Meximelt had 270 calories (from Fat - 130), 14g of fat (Saturated Fat - 7g), 760mg of sodium, 21g of carbs (2g from sugar), and 14g of protein.