01 -
Combine diced tomato, chopped red onion, spinach, crumbled feta, shredded mozzarella, and dried oregano in a medium bowl. Gently toss to mix evenly. Squeeze spinach with hands to remove excess moisture to prevent sogginess.
02 -
Lay the three flour tortillas on a work surface. Evenly divide the filling, placing approximately half of the filling on one side of each tortilla. Fold tortillas in half over the filling, pressing gently to secure and distribute filling edge to edge.
03 -
Heat a large skillet over medium heat and lightly coat with olive oil. Place folded quesadillas in the skillet. Cook 3-4 minutes per side until golden brown and cheese is melted. Cook in batches if necessary to avoid overcrowding.
04 -
Transfer cooked quesadillas to a cutting board and rest for 1 minute to allow cheese to set. Cut each quesadilla into halves or triangles and serve immediately while warm.