Heat the oil in a large pot over medium-high heat. Add in the artichoke pieces and cook for one minute. Reduce heat to medium, add in the spinach, and cook until wilted, turning often. Mix in the cream cheese and mozzarella and Parmesan cheeses, and let it melt entirely while stirring. Season with salt and pepper to taste. Remove from heat.

Spread about ¼ cup of the mixture on 4 of the tortillas, then top with remaining tortillas.

Heat a large skillet over medium heat, add each quesadilla and heat for 1-2 minutes per side, until crisp; careful not to burn.

Remove from skillet and repeat for all quesadillas. Cut into 4ths and serve.