Preheat oven to 400F. Line a large baking sheet with parchment paper. Add panko and cheese to a large bowl and then mix together until thoroughly combined. Dip cauliflower in egg mixture and then shake a few times so that excess egg drips off. You don't want to dampen your breadcrumbs with excess egg because then they won't stick to the cauliflower. Then roll in bread crumb mixture until fully coated and place on a baking sheet lined with parchment paper. You may need to press on the coating to help get it to stick to the cauliflower bites. Repeat until all cauliflower is coated. Bake for about 20-25 minutes until coating is a dark golden brown and crunchy. Sprinkle with parsley. Serve with marinara sauce.