Classic Beef Stroganoff with Rump Steak

Rump is the classic butcher's choice for a quick stroganoff, with a deep beefy flavour and enough texture to hold its shape in the sauce. Rostbiff is the trimmed centre of the rump, so it gives neat, even strips with very little waste. A whole grass-fed rump is made up of several muscles with slightly different grains, so separate them along the natural seams and check the grain direction before you slice. For a special-occasion version, use strips of eye fillet and sear them for just 30 seconds per side. Slice thickness matters more than anything else here. Strips about 1cm thick brown on the outside before the centre overcooks, while very thin strips turn grey and chewy in seconds. The three most common mistakes are crowding the pan, which steams the beef instead of searing it, cooking the strips all the way through in the first sear, and boiling the sauce once the sour cream is in. Full-fat sour cream at room temperature is the most stable, and if the sauce does split, take it off the heat and whisk hard with a splash of cold stock. This is the quick, pan-seared steak version. Got leftover roast beef? It becomes a creamy roast beef stroganoff in minutes, while a slow-cooked stroganoff braises chuck or blade for hours. Buying a whole rump also covers steaks and a roast later in the week, which is one of the easiest ways to stretch a budget across several cheap meat dinner ideas. To get ahead, cook the sauce to the end of step 4, cool it and keep it covered in the fridge for up to 2 days. Reheat it gently, add the sour cream off the heat and sear the beef fresh. Refrigerate leftovers within two hours, eat them within 2 to 3 days and reheat over low heat without boiling. Sour cream sauces can turn grainy in the freezer, so freeze the sauce before the sour cream goes in. Doneness guide for steak after resting: rare 55 to 60C, medium rare 60 to 63C, medium 65 to 70C, well done 75C. Pull it 3 to 5C below your target, because it keeps cooking as it rests. The strips in this recipe are seared until browned outside and pink inside, then finish cooking gently in the hot sauce. The Food Safety Information Council recommends cooking whole cuts of beef to at least 63C and resting them for 3 minutes. Rarer beef is a personal choice that pregnant women, older people, young children and anyone with a weakened immune system are safest avoiding, so let the strips simmer in the sauce for an extra 2 minutes when you are cooking for them.