Preheat oven to 425.Combine first 5 ingredients in a medium bowl, stirring with a whisk.
Place milk in a shallow bowl. Dip zucchini slices in milk, and dredge in dry mixture.
Place coated slices on an oven proof wire rack coated with cooking spray; place rack on a baking sheet.
Bake at 425 for 30 minutes or until browned and crisp.
Serve immediately.