Heat the oven to 150C/Gas Mark 2. Dust the pieces of stewing steak all over with flour and season with salt and pepper. Heat a heavy-based ovenproof sauté pan over a medium-high heat and add a good drizzle of olive oil.
Brown the steak in two batches for 4-5 minutes until well caramelised. Remove with a slotted spoon and set aside. Return the pan to the heat and add another drizzle of oil. Add the onion, carrots and mushrooms, lower the heat and sweat gently for 4-5 minutes. Add the garlic and bouquet garni.
Pour in the red wine and allow to bubble to reduce by half, then add the Yer Ben beer. Bring back to the boil and return the steak to the pan. Put a lid on the pan and place in the oven. Cook for 3 hours or until the steak is tender and the liquor has reduced and thickened.
Raise the oven setting to 180C/Gas Mark 4. Transfer the beef stew to a pie dish, discarding the bouquet garni.
Place a piece of bone marrow in the middle of the dish. Roll out the pastry to fit the dish with enough to overhang, then drape over the stew. Dampen the rim of the dish with water, then lift the pastry over the top of the stew. Press the edges of the pastry on to the rim of the dish and trim away the excess pastry. Brush the pastry all over with the egg wash, sprinkle with sea salt and black pepper and bake for around 20 minutes until the pastry is golden brown and crisp.
Leave to rest for 10 minutes, then serve the pie with seasonal vegetables and teaspoons for the bone marrow, for those who want it.
1kg stewing steak, cut into 2–3cm pieces
flour for dusting
sea salt and freshly ground black pepper
olive oil for cooking
1 onion, peeled and diced
2 carrots, peeled and chopped
250g button mushrooms, cleaned
2 garlic cloves, peeled and chopped
250ml red wine
500ml Yer Ben craft ale
250g ready-rolled puff pastry
egg wash (1 egg yolk beaten with ½ teaspoon water and a pinch of salt)