Heat 3 tbsp fat in a large (ideally cast-iron) frying pan over medium-high heat.
Beat the eggs with the salt, pepper and paprika, dip in the steaks, then coat both sides thoroughly in flour.
Fry the steaks for about 4 minutes per side until golden, then keep warm in a 90 °C oven.
Add the remaining fat to the pan, turn the heat down, sprinkle in 3 tbsp flour and cook, whisking, until pale blond.
Pour in the stock, scrape up the browned bits, add the milk and cream, bring to the boil and simmer until it coats a spoon; pour over the steaks and serve.