Preheat your oven to 350°F (180°C) and grease an 8x6 inch baking dish with olive oil.

Slice the zucchini lengthwise and grill for 3-5 minutes on each side until tender.

Melt butter in a pot, whisk in flour and milk to create a white sauce. Cook until thickened.

In a bowl, mix drained tuna, bread crumbs, mozzarella, egg, parmesan, olive oil, salt, pepper, and parsley.

Layer half of the grilled zucchini in the baking dish, followed by tuna mixture and half the white sauce. Repeat layers.

Bake for 20-25 minutes until golden brown and bubbly.

Let the lasagna cool for 5 minutes, then slice and serve.