Heat panini press or a large skillet over medium.

Spread mustard onto tortillas; add shredded cheese, ham and spinach to each. Fold each tortilla in half and cook until cheese has melted. Cut into halves or quarters. If packing quesadillas into lunchboxes, be sure to allow to cool completely first.

Cut celery and carrot into sticks, and apples into slices. Serve with quesadillas.