Add the olive oil into a large non-stick frying pan on a high heat. Preheat the oil and then add the mushrooms into the pan. Refrain from stirring for around 5 minutes so that you get as much browning as possible, I fried my mushrooms in batches of two to maximise browning.
Once the mushrooms have cooked, remove from the pan and reduce the heat, stirring the onions & thyme into the pan with a pinch of salt. Continue to gently fry until the onions are translucent, this will take around 6 minutes.
During this time, add your pasta to salted boiling water, timer set according to the packet time minus 2 minutes. For me, this was 8 minutes.
Now that the onions are translucent, add the minced garlic, gently frying for a minute before adding the cream and mushrooms back into the pan. Heat through and then add the beef stock and worcester sauce. Gently simmer whilst the pasta cooks.
When the pasta timer about to go off, add the cornflour slurry into the sauce and heat until thickened.
Transfer the undercooked pasta into the sauce and continue to cook on a low heat. Loosen with reserved pasta water if necessary and add the juice of half a lemon (more to taste) and stir to form the delicious stroganoff sauce. Continue to cook until the pasta is al dente and serve with lots of black pepper.
Top with fresh parsley & dig in!