1. Fry the pork steaks in a small amount of olive oil and butter, until browned.
2. Add the sliced mushrooms, lower the heat and toss in the pan juices.
3. Add the flour and cook for 2 minutes.
4. Stir in the red wine and grainy mustard and bring to the boil.
5. Gradually add enough vegetable stock to make a gravy, season and simmer, until the pork is cooked through.