Serves 3–4

Time 45 mins

Ingredients:

1 beef flank steak (900 g–1 kg), butterflied if needed 

olive oil

sea salt & freshly ground black pepper

200g wild mushrooms (chestnut, shiitake, oyster), finely chopped

2 large onions, thinly sliced 

2 garlic cloves, finely chopped

150g spinach 

small knob of butter (optional)

a few rosemary sprigs

Method:

Pre-heat the oven to 200deg C (400def F).

Lay the butterflied flank steak flat, drizzle with olive oil, and season both sides generously with sea salt and cracked black pepper.

In a hot pan with a splash of olive oil, sauté onions until caramelised. Add the garlic and cook briefly, then stir in the chopped mushrooms. Season and cook until moisture evaporates. Toss in spinach until wilted. Optionally, add a knob of butter for richness. 

Spread the mushroom-spinach mixture evenly over the steak. Roll tightly from one end and secure with kitchen twine. 

Sear the rolled steak on all sides in a hot pan with olive oil and rosemary sprigs to infuse the flavour. Then, roast in the oven at 200°c (400°f) for 20–25 minutes for medium-rare.

Let it rest for 10 minutes before slicing into thick, juicy rounds.

Chef notes

• Add a smear of dijon mustard on the steak before adding the filling for depth.
• Try 'dry brining' the steak with salt a few hours before cooking; it intensifies flavour and softens texture. 
• Swap spinach for kale for texture.
• Add crumbled blue cheese to the filling for a spicy bite.
• Finish with a drizzle of balsamic reduction for a sweet-tangy contrast.