I needed a good tuna melt recipe – maybe this is my new favorite!

- Tuna, 2 x 5-oz cans, drained
- Onion, medium size, chopped
- Celery, 1/2 a stalk, chopped
- Garlic (1 clove), minced
- Parsley, 1 tablespoon, chopped
- Mayonnaise, 3-4 tablespoons
- Extra Virgin Olive Oil, 3 tablespoons, divided
- Mozzarella, 1/3 cup, shredded
- Bread, sliced
- Butter, softened
- Salt and Pepper to taste