Bring a large pot of salted water to the boil. Add the egg noodles and cook until just al dente. Drain well and set aside.
Prepare The Beef
For easier slicing, place the beef in the freezer for 30 minutes. Slice into thin strips across the grain. Pat dry with a paper towel, then season with salt and black pepper. Dust lightly with flour to aid browning and help thicken the sauce.
Sear The Beef
Heat olive oil in a large skillet over medium-high heat. Working in batches, sear the beef strips for 1–2 minutes per side, until they are browned. Remove to a plate and repeat until all the beef is seared.
Build The Sauce
In the same skillet, melt the butter. Add the onions and mushrooms, cooking for 6–8 minutes until softened and golden. Stir in the garlic and paprika, cooking for 30 seconds. Deglaze the pan with beef stock, scraping up any browned bits, and simmer for 5 minutes to reduce the liquid.
Finish The Stroganoff
Lower the heat and stir in Worcestershire sauce, Dijon mustard, and sour cream. Mix until smooth and silky. Return the seared beef and any juices to the pan, tossing gently to coat the beef. Stir through the chopped parsley to finish.
Assemble The Meal Prep
Divide the noodles evenly into five containers. Top each with a generous portion of beef stroganoff and sauce. Garnish with extra parsley and cracked black pepper.
Chef's Tips
Freeze the beef for the full 30 minutes before slicing, and always cut against the grain — this is what makes the strips easy to slice thin and gives you tender beef rather than something chewy once it's in the sauce.Sear the beef quickly in batches, no more than 1–2 minutes per side, and don't crowd the pan — these are thin strips, so they'll toughen fast if overseared now or left in the sauce too long later.Lower the heat before stirring in the sour cream, and keep it well below a boil once it's in — sour cream splits more readily than regular cream, so gentle heat here is what keeps the sauce smooth rather than grainy.
Storage & Reheating
Refrigerate for up to 4 days, or freeze for up to 3 months, in an airtight container. Sour cream sauces can separate slightly once frozen and thawed, so give them a good stir while reheating to bring them back together.To reheat, warm gently in a pan over low heat or in the microwave in short bursts, stirring in a small splash of water or stock as needed to loosen the sauce. Thaw frozen portions in the fridge overnight before reheating.