Combine the first 10 ingredients in a large saucepan; bring to a boil. Reduce heat, and simmer 20 minutes or until zucchini is tender. Stir in spinach; cook 1 minute or until spinach wilts. Let stand 5 minutes. Place half of zucchini mixture in a blender, and pulse until coarsely pureed. Pour pureed zucchini mixture into a large bowl. Repeat the procedure with remaining zucchini mixture. Stir in half-and-half. Ladle soup into bowls; sprinkle with cheese.