In a large bowl, place Parmesan cheese and 2 tbsp of chives. Add egg and mix until combined. Add mashed potatoes and 35g of flour and mix again until combined. Place the bowl with the mix into the fridge for about 10 minutes.
Place the remaining flour on a shallow plate or dish, divide the potato mixture into 8 equal portions. Using your hands, shape each portion into a patty, dredge each patty in flour on both sides, gently shaking off any excess.
Heat the olive oil in a frying pan and fry patties until golden brown on both sides (about 3 minutes on each side). Top with sour cream and more chives and enjoy!