BBQ flank steak with onions, mushrooms, tarragon and horseradish sauce
- Prepare
- less than 30 mins
- Cook
- 10 to 30 mins
- Serve
- Serves 2
This chargrilled flank steak is served with smoky onions and mushrooms, then finished with a creamy tarragon and horseradish sauce. It’s a good barbecue main, but you could also cook it on a hot griddle pan.
Ingredients
For the BBQ flank steak, onions and mushrooms
- 2 red onions, cut into thick rings
- 1 portobello mushroom, sliced
- 4 oyster mushrooms, cut in half
- 1 tsp chopped thyme leaves
- 1 garlic clove, crushed
- 250g/9oz flank steak
- olive oil, for drizzling
- salt and freshly ground black pepper
For the tarragon and horseradish sauce
- 45g/1½oz unsalted butter
- 1 banana shallot, finely chopped
- 1 garlic clove, finely chopped
- 100ml/3½fl oz white wine
- 50ml/2fl oz white wine vinegar
- 150ml/5fl oz chicken stock
- 100ml/3½fl oz double cream
- 3 tbsp freshly grated horseradish
- 1 tbsp chopped tarragon
Method
To make the BBQ flank steak, onions and mushrooms, preheat a griddle pan until hot.
Season the onions and mushrooms with salt and pepper. Char grill the vegetables for about 5–8 minutes, turning regularly, until soft and cooked through.
Transfer the onions and mushrooms to a bowl. Add a drizzle of olive oil, the thyme and garlic. Cover with foil and leave to steam while you cook the steak.
Season the steak with salt and pepper. Place on the griddle pan for 2 minutes on each side, or until cooked to your liking. Transfer to a board and leave to rest for at least 5 minutes before serving.
To make the tarragon and horseradish sauce, melt the butter in a saucepan over a medium heat. Add the shallot and garlic and cook gently until softened.
Add the wine and simmer until reduced by half. Add the vinegar and simmer again, then add the chicken stock.
Add the cream and horseradish and bring to the boil. Stir in the tarragon, then taste and season with salt and pepper if needed.
Slice the steak thinly against the grain. Toss with the onions, mushrooms and any resting juices. Remove the clove of garlic before serving.
Serve the steak, onions and mushrooms with the tarragon and horseradish sauce spooned around.
Recipe tips
If you don’t have a barbecue, cook the steak, onions and mushrooms on a very hot griddle pan.
