Heat the butter and olive oil in a deep pan and fry the fillets that have been rolled in salt, pepper and flour on both sides. Remove them and cover with aluminum foil in a plate.
In the same pan, add the wine, lower the heat and cook until the wine is reduced to 2 tablespoons. Then add the cream, vegetable broth, mustard and stir the sauce for about 5 minutes, until thickened.
Season with salt and pepper. Serve the pork fillets, coated with sauce.