Slice the pork tenderloin into 5cm (2 inch) thick medallions.
Flatten each medallion using your palm.
Heat olive oil and 1 tbsp butter in a large frying pan over medium high heat.
Once butter is melted add pork medallions and cook until browned, about 2-3 minutes each side. Remove from pan and set aside. Keep warm.
Add remaining 2 tbsp butter to the pan and once melted add spring onions and cook for about 1 minute. Stir occasionally.
Add garlic and cook a further 30 seconds. Be careful not to burn the garlic.
Add mushrooms and stir to coat with butter. Cook for about 3 minutes only stirring occasionally. Continue cooking until mushrooms have browned and liquid has mostly evaporated.
Sprinkle the flour over the mushrooms and stir to mix through. Cook a further 2 minutes.
Add wine and stir to mix through. Continue cooking until wine has nearly evaporated.
Add chicken stock, stir to mix through and cook for a further 4-5 minutes.
Reduce heat to low, add cream and parley. Stir to mix through.
Add pork medallions back into the pan and cook a further 3-4 minutes. Season with salt and pepper. Only turn the medallions once.
Serve pork over pasta or mashed potatoes and spoon mushroom sauce over pork.