Beat the two egg whites loosely in a mixing bowl, do not let them become too stiff. Then put in a cool place.
In a mixing bowl, beat the flour, milk, crème fraîche, salt and egg yolk to a smooth batter. Let this dough rest for approx. 25 minutes.
Rinse the pangasius fillets under running water and then pat dry with kitchen paper. Season with salt and drizzle with lemon juice.
Now fold the egg white, beaten until stiff, into the dough.
Pull the pangasius fillets through the batter so that they are completely coated and then fry them well golden brown in a pan in rapeseed oil over medium heat.