Combine egg, onion, parmesan, pepper, and salt in a medium bowl with a fork until well mixed

Place rice flakes in a seal-able plastic bag. Crush cereal with a rolling pin until medium coarse. Add to egg mixture until combined

Add ground turkey, and stir to combine

Lay down a sheet of wax paper, and spoon mixture on top. Press with fingers to form a rectangle, 1/2 inch thick

Cut mixture into 30 1 inch squares. Form squares into 1 1/4 inch meatballs

Spray baking sheet with cooking spray, and place the meatballs on the sheet, half an inch apart

Bake at 375 for about 20 minutes until no longer pink