01 -
Preheat your oven to 200°F (95°C). This low temperature will keep your finished quesadillas warm while you cook the remaining ones.
02 -
Heat the olive oil in a large skillet over medium-high heat. Add the ground beef, spreading it out into smaller chunks across the pan. Cook for 2-3 minutes without stirring until the bottom is nicely browned. Flip the meat and break it into smaller pieces with a spatula.
03 -
Add the diced onions and bell peppers to the skillet with the beef. Continue to sauté for another 3-4 minutes, or until the beef is completely cooked through and the vegetables have softened. Drain any excess grease from the pan.
04 -
Sprinkle the taco seasoning evenly over the beef and vegetable mixture. Add the water and tomato sauce, then stir until everything is well combined and the sauce has thickened slightly. Transfer the beef mixture to a plate and set aside.
05 -
Wipe out the same skillet and place it over medium heat. Add a small portion of the butter (about ½ tablespoon) to the pan and swirl to coat the bottom and edges.
06 -
Place one flour tortilla in the buttered pan. Sprinkle about 1 cup of shredded cheese evenly across the entire tortilla. Heat until the cheese just begins to melt, about 2 minutes. Add one-quarter of the beef mixture to one half of the tortilla only.
07 -
Using a spatula, carefully fold the cheese-only side of the tortilla over the beef-filled side to create a half-moon shape. Press down firmly with the spatula to help the cheese melt into the filling and seal the edges.
08 -
Cook the folded quesadilla for another 1-2 minutes until the bottom is golden brown, then flip and cook the other side for an additional 1-2 minutes until crispy and golden.
09 -
Transfer the finished quesadilla to a wire rack placed in your preheated oven to keep warm. Repeat the process with the remaining tortillas, beef mixture, and cheese, adding a small amount of butter to the pan before each new quesadilla.