Sheet pan cheesy beef quesadillas are baked in one big batch in the oven. soft flour tortillas are loaded with ground beef filling, seasoned with Mexican taco seasonings, roasted red peppers, optional homemade salsa and melted gooey cheese. This will be your no.1 quesadilla recipe!
Preheat oven to 450°F. Spray a large 9x13 inch baking sheet with cooking spray. Cover the sheet pan in foil or parchment paper if you like then spray the foil/parchment paper with the cooking spray.
In a small bowl add the water and flour and mix well until the clumps have disappeared. Set to the side.
Heat large skillet over medium high heat until hot. Add ground beef; cook until browned. Drain all but 2 tablespoons of the fat from the beef. Do not turn off the stove. Add the seasoning mix (see notes), salsa and tomato sauce. Add the slurry and mix until the ground beef mixture thickens. Reduce to simmer for 5 minutes. Cool for 10 minutes.
Cover the baking sheet with half of the flour tortillas, trimming to fit. Sprinkle cheese and cooled ground beef.
Place the baking sheet in the oven for a couple minutes. Remove pan from the oven. Top with the roasted red peppers and more cheese. Add the rest of the trimmed tortillas on top of the cheese. Bake for a couple of minutes.