Peel and cut the potatoes into chunks. Boil in water until fork-tender (assumption: 12–15 minutes), then drain very well.
Mash potatoes with butter, salt, black pepper, red pepper flakes, garlic powder, dried parsley, breadcrumbs, and onion powder until smooth and moldable. Let cool until easy to handle.
Mix cream cheese and mozzarella together for the filling (or keep mozzarella as the center if preferred). Set up three bowls: flour, beaten eggs, and breadcrumbs.
Scoop potato mixture, flatten, add cheese filling, then pinch closed and roll into a tight ball.
Coat each ball in flour, dip in egg, then roll in breadcrumbs. Press gently so crumbs adhere.
Heat oil to 350°F (175°C) (assumption). Fry in batches until deep golden brown (assumption: 3–4 minutes), turning as needed.
Drain on paper towels and serve hot.
