Heat a large skillet over medium heat and add a tablespoon of olive oil.

Add 2 cups of chopped fresh spinach to the skillet and sauté for about 2-3 minutes until wilted.

Combine sautéed spinach with 1 cup of crumbled feta, ½ cup of shredded mozzarella, ½ cup of chopped sun-dried tomatoes, and ¼ cup of sliced olives in a mixing bowl.

Place one tortilla in the preheated skillet and spread half of the filling mixture on one half, folding it over.

Cook for 3-4 minutes on one side until golden brown, then flip and cook for an additional 3-4 minutes.

Remove quesadilla, let it cool slightly, then cut into wedges and serve.