Sear the Beef: Pat the beef strips dry with a paper towel and season generously with salt and pepper. Heat the olive oil in a large, heavy-based frying pan or skillet over a high heat. Once the pan is very hot, add the beef in a single layer (work in two batches if necessary to avoid overcrowding). Sear for 1-2 minutes on each side until beautifully browned. Do not overcook. Remove the beef with a slotted spoon and set aside on a plate.

Sauté the Aromatics: Reduce the heat to medium. Add the butter to the same pan. Once melted, add the chopped onion and cook for 5-7 minutes, stirring occasionally, until softened and translucent. Add the minced garlic and cook for another minute until fragrant.

Cook the Mushrooms: Add the sliced mushrooms to the pan. Turn the heat up slightly and cook for about 5-8 minutes, until they have released their liquid and started to brown and caramelise. Those golden edges are pure flavour!

Create the Sauce Base: Sprinkle the plain flour and smoked paprika over the mushrooms and onions. Stir continuously for 1 minute to cook out the raw flour taste. This mixture, called a roux, will thicken our sauce.

Deglaze and Simmer: Gradually pour in the hot beef stock, stirring constantly to avoid lumps. Scrape any browned bits from the bottom of the pan. Bring the mixture to a gentle simmer, then stir in the Worcestershire sauce and Dijon mustard. Let it bubble away for 3-4 minutes until the sauce has thickened slightly.

Bring It All Together: Return the seared beef and any accumulated juices to the pan. Stir everything together and let it warm through for a minute.

Add the Creaminess: This is the most important step! Take the pan completely off the heat. Let it cool for a minute. What works best for me is to then stir in the room temperature soured cream and crème fraîche. Stir gently until the sauce is smooth, pale, and velvety. Taking it off the heat ensures the dairy won't curdle.

Serve: Season the stroganoff with salt and pepper to your taste. Stir through most of the chopped fresh parsley, reserving a little for garnish. Serve immediately over egg noodles, pasta, or fluffy rice.