Celeriac and beef stroganoff with crispy thyme crumbs

Method

1. Simmer the celeriac in the stock in a medium pan with the lid on until very soft (about 20 minutes). Don’t let it boil rapidly – you don’t want to evaporate the liquid.
2. Put a large frying pan over a medium-high heat with 1 tbsp of the olive oil. Once hot, add the sliced steak and sear all over until just browned. Remove from the pan and add the onion with a pinch of salt. Fry for 7 minutes, stirring often, then add the garlic and fry for a minute more. Add the sliced mushrooms. While they’re cooking – keep an eye on them to avoid burning – transfer the cooked celeriac and its stock# to a blender and whizz until
   smooth. Taste and add salt and a squeeze of lemon juice.
3. Put a small frying pan over a high heat with the remaining olive oil and, once hot, add the crumbs and thyme along with plenty of salt and pepper. Stir often until the crumbs have an even golden colouring, then take off the heat.
4. Meanwhile, stir the tomato pureé, mustard and smoked paprika into the mushrooms and cook for 1 minute. Add the wine or brandy and leave to reduce by half. Return the steak to the pan (along with any resting juices) and stir in the celeriac purée. Serve with the crispy thyme crumbs sprinkled over the top.