Cut zucchini in half lengthwise, remove seeds. Place cut side down on a baking sheet and bake until tender. Or you can microwave until tender.
Scoop out pulp, leaving a quarter inch shell. Finely chop zucchini and set it aside.
cook onion in hot oil until tender, not browned. Add zucchini and cook for 1 minute. Stir in flour, basil and pepper. Add milk and stir until thickened and bubbly. Add egg and stir in parmesan cheese.
spoon mixture into zucchini shells and place in a baking dish. Bake