Check the pork fillet and remove/trim any membrane and fat.
Slice the pork fillet into bitesize pieces.
Place a large frying pan over a high heat and add 2 tsp of the oil. When hot add about 1/2 of the pork and stir fry very quickly. When nicely browned, remove form the pan and put to one side.
Repeat with the remainder of the pork and put to on side with the rest. Frying the pork in two batches keeps the pan hot and the browning faster.
Reduce the heat to medium and add the French onion soup. Stir the soup making sure all of the tasty goodness from the pork stir fry is loosened from the bottom of the pan. Don't want to leave anything behind. bring the soup u[p to a simmer.
Add the crème fraiche and mustard and continue to simmer for about 5 - 7 minutes. The sauce should become richer and also reduced in volume. Reduction means intensity in flavour.
When ready, return th stir fried pork to the pan with the resting juices and heat for 1 -2 minutes. The pork is cooked so you only want to heat it up not cook it more.
Taste the sauce and season with salt and pepper to your liking. Always add salt a little bit at a time and re taste.
Add 3/4 of the parsley and stir thoroughly.
Serve on a bed of piping hot rice and the remainder of parsley scattered on as a garnish.