Heat oven to 475 F; grease cookie sheet. Stir cornmeal, pepper, and cayenne and garlic powder together in one bowl. In another bowl, whisk the eggs. Dip zucchini slices into beaten egg and coat them with the cornmeal mixture. Place on a greased cookie sheet and bake for 5 minutes; turn and bake for another 5-10 minutes, until browned and crispy.