Beef Stroganoff

Peel and slice the onion. Clean and quarter the mushrooms.

Pat the beef strips dry with kitchen paper. Heat a pan over a medium-high heat with a drizzle of oil. Once hot, add the beef strips and salt. Fry for 2 min without moving the beef in the pan. Turn the beef and cook for 2 min further. The beef strips don't need to be fully cooked. Transfer them to a plate and reserve the pan.

Bring a large pot of salted water to a boil. Once boiling, add the tagliatelle and cook for 9-12 min until 'al dente' or cooked to your liking. Reserve half a cup of the pasta water. Meanwhile, chop the chives and set them aside for garnish. 

Return the reserved pan to a medium-high heat with the butter. Add the onion, garlic paste and a pinch of salt, cook for 3 min. Add the mushrooms with a pinch of salt and cook for 7 min or until golden. Scrape the bottom of the pan to loosen any brown bits.

Reduce the heat to medium and add the flour. Stir. Add the stock and whisk. Simmer for 2 min. Return the beef strips along with any juices. Add the Dijon mustard, Worcestershire and sour cream (reserve some for garnish). Cook for 5 min further. 

Finally, season the stew with salt and pepper. Use the reserved pasta water to adjust the sauce consistency if too thick. Divide the tagliatelle among plates. Top with the Stroganoff stew and garnish with the reserved sour cream and the chopped chives.