Spritz a large skillet with cooking oil (I use avocado oil spray). Or add a drizzle of olive oil. Turn the stove-top burner to medium-high heat.
Add the ground beef to the hot skillet. Break up the ground beef with a wooden spoon and cook, stirring every couple of minutes, for 5 minutes.
Once mostly cooked, with just a bit of pink left in the ground beef, drain grease/fat from the skillet.
Evenly sprinkle the taco seasoning over the beef, then add the water. Stir the seasoning and water into the ground beef until well incorporated. Simmer for 3-4 minutes, until the water has cooked out. Turn off the heat.
Assemble the Quesadillas
Place 4 tortillas on a sheet pan.
Sprinkle cheese (2 tablespoons) over half of each tortilla. Add 1/2 cup cooked ground beef mixture over the top of the cheese, followed by 2 more tablespoons of cheese over top the ground beef. Fold each tortilla over the filling.
Cook the Quesadillas
Spritz the top of each quesadilla with oil (just a spritz). Place the quesadillas in the oven, under the broiler.
Cook for 3-4 minutes on one side, or until the tops of the tortillas appear golden and crisp. Remove from the oven and use a spatula to flip the tortillas. You shouldn't need to spritz this side with oil. Place the quesadillas back under the broiler and cook for another 3-4 minutes, or until the tops are golden brown and crisp and the cheese has fully melted. The amount of time it takes for the quesadillas to cook will depend on your oven and broiler--keep a close eye on them. They cook fast!
Remove from the oven and enjoy warm! Enjoy whole, or allow the quesadillas to cool for a few minutes (about 3-4 minutes), then use a sharp knife to cut the quesadillas into 2-4 pieces.
Top with any toppings desired.
Notes
To make your own taco seasoning, enough for just this recipe, mix together...
1 tablespoon chili powder
1/2 tablespoon ground cumin
3/4 teaspoon paprika
3/4 teaspoon salt
1/4 teaspoon garlic powder
1/4 teaspoon onion powder
1/4 teaspoon oregano
1/4 teaspoon black pepper
Nutritional value is based on using 85/15 ground beef, a flour tortilla, and no toppings.