Combine your flour and beef in a ziplock bag along with salt and pepper. Shake the bag to fully coat and season the meat.
Place half of your butter and olive oil in a large frying pan. Cook over high heat until the mixture starts bubbling.
Cook half of your beef stirring it for 3 to 5 minutes or until it turns brown. Once cooked place the beef on a plate.
Repeat this step with the remainder of your butter, oil and beef.
Reduce the heat of your pan to medium and heat the remainder of your oil in pan.
Add your onion and mushrooms to the pan and stir it for 5 minutes or until cooked.
Add in your garlic and paprika stirring it for 1 minute.
Add in the wine, beef stock, mustard, tomato paste and beef into the pan.
Stir to combine all of the ingredients and then bring it to boil.
Once boiled, reduce the heat to low and simmer for 5 minutes or until the sauce has thickened slightly.
Stir in the crème fraiche and serve the dish over pasta or mashed potatoes with parsley.