Stuffed Zucchini

1 pound lean ground beef
1 large onion, chopped
3 cups cubed French bread
1 (10 ounce) package frozen chopped spinach, thawed and squeezed dry
1/2 cup minced fresh parsley
1/2 cup tomato sauce
1/4 cup shredded Parmesan cheese
1 egg, beaten
1 teaspoon salt
1/2 teaspoon dried thyme
6 medium zucchini
1 cup water
Directions

In a large skillet, cook beef and onion over medium heat until meat is no longer pink; drain. Stir in the bread cubes, spinach, parsley, tomato sauce, Parmesan cheese, egg, salt and thyme; set aside.
Cut each zucchini in half lengthwise. Scoop out seeds, leaving a 1/4-in. shell. Spoon about 6 tablespoons beef mixture into each zucchini half. Place in two ungreased 13-in. x 9-in. x 2-in. baking dishes. Pour 1/2 cup water into each dish. Cover and bake at 350 degrees F for 30 minutes. Uncover; bake 10 minutes longer or until zucchini is tender.