Preheat the grill to medium heat, around 350°F (175°C) and oil the grill grates.

Combine sliced zucchini, red bell pepper, and red onion with olive oil, salt, pepper, and oregano in a mixing bowl.

Arrange the seasoned veggies on the grill and cook for about 5 to 7 minutes until tender and charred.

In a skillet, sauté minced garlic in olive oil and then add fresh spinach; cook until wilted.

Layer grilled veggies, sautéed spinach, halved cherry tomatoes, crumbled feta, and shredded mozzarella on half of each tortilla and fold.

Grill the quesadillas for 3 to 4 minutes on each side until golden brown and cheese melts.

Let the quesadillas rest for about 5 minutes before slicing into wedges.

Serve warm with tzatziki, salsa, or hummus for dipping.