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 breadcrumb mixture.
Place coated slices on an ovenproof wire rack coated with cooking spray; place rack on a baking sheet.
Bake at 220°C for 30 minutes or until browned and crisp. Serve immediately.