Wash the fillets, dry them cut into pieces. Arrange them in an oiled tray. Sprinkle with salt and black pepper, pour the lemon juice on top.
Cover with pieces of butter and round slices of onions. Cover the tray with aluminum foil and put it in a preheated 428°F (220 °C) oven until the meat is ready.
Pour out the juice that's released during baking and mix it with the wine, cream, flour and almonds.
Pour it over the fillets and put them back in the oven briefly. Cover the now-ready dish and leave it for a bit before serving.