BEEF FILLET WITH HORSERADISH BUTTER & GRILLED MUSHROOMS

SERVES 4

The horseradish butter in this recipe is also delicious with grilled chicken and salad.

800 g (1 lb 12 oz) beef fillet

sea salt and freshly ground black pepper

extra virgin olive oil

4 large flat mushrooms, stems trimmed

HORSERADISH BUTTER

1 tablespoon finely grated fresh horseradish (or good-quality jarred)

small handful flat-leaf (Italian) parsley leaves, roughly chopped

3 teaspoons dijon mustard

juice of 1 lemon

freshly ground white pepper

250 g (9 oz) room-temperature butter, chopped

LEMON THYME OIL

½ bunch lemon thyme, leaves picked and finely chopped

1 garlic clove, finely chopped

150 ml (5 fl oz) extra virgin olive oil

sea salt and freshly ground white pepper

Preheat the oven to 200°C (400°F/Gas 6).

For the horseradish butter, use a food processor to mix the horseradish, parsley, mustard, lemon juice and a pinch of white pepper for about 1 minute or until well combined. Add the butter and process for a further 30 seconds or until just combined. Roll the butter mixture in sheets of baking paper into a log shape about 4 cm (1½ inches) in diameter. Refrigerate until firm.

Season the beef with salt and pepper. Heat a heavy-based frying pan over high heat and add a splash of olive oil. Seal the beef on all sides until browned. Bake in the oven for 10–15 minutes or until desired doneness. Allow to rest for 10–15 minutes before slicing.

For the lemon thyme oil, mix all the ingredients in a bowl until combined. Season to taste.

In a non-stick frying pan, heat half of the lemon thyme oil and add the mushrooms, stem side down. Cook for 3–4 minutes over medium heat until golden. Turn over, and brush the insides of the mushrooms with the remaining lemon thyme oil and cook until the mushrooms are tender.

Serve the beef sliced with a disc of the horseradish butter and a grilled mushroom.

NOTE: Use a meat thermometer to cook the beef. When the temperature of the beef is 52°C (125°F), rest it for 10–15 minutes for rare. Rest at 55°C (131°F) for medium rare and 60°C (140°F) for well done.