Longhorn Beef Sirloin Recipe with Charred Onions
by Merlin Labron-Johnson
4
1 hour 30 minutes
Ingredients

Beef sirloin

  • 600g of aged sirloin of beef
  • 50g of salted butter, high-quality
  • olive oil
  • flaky sea salt

Tropea onions

  • 5 Tropea onions, large
  • red wine vinegar
  • olive oil
  • salt

Pickled walnut salsa verde

  • 1 bunch of parsley, small, finely chopped
  • 100g of walnuts, toasted and finely chopped
  • 6 pickled walnuts, finely chopped
  • 400ml of light olive oil
  • 1 tbsp of Dijon mustard
  • 1 tbsp of capers, finely chopped
  • 1 anchovy, finely chopped
  • lemon juice, if needed

To serve

  • watercress
  • olive oil
  • salt
Method
1
Preheat the oven to as high as it can go
2
To begin, prepare the onions. Place the onions whole onto a large square of tin foil and season with salt and oil
  • 5 Tropea onions, large
  • olive oil
  • salt
3
Fold the tin foil over the onions to create an envelope and seal the edges. Bake in the oven for 40–55 minutes until cooked but not soft. Set aside
4
To make the salsa verde, mix together all of the ingredients and season with salt, plus a little lemon juice if needed
  • 1 bunch of parsley, small, finely chopped
  • 100g of walnuts, toasted and finely chopped
  • 6 pickled walnuts, finely chopped
  • 400ml of light olive oil
  • 1 tbsp of Dijon mustard
  • 1 tbsp of capers, finely chopped
  • 1 anchovy, finely chopped
  • lemon juice, if needed
5
To prepare the sirloin, rub the beef with oil and salt and set aside in a warm place until it reaches a temperature of approximately 45°C
  • flaky sea salt
  • 600g of aged sirloin of beef
  • olive oil
6
Heat a heavy-bottomed cast iron pan until smoking hot and sear the beef on 1 side for 1 minute
7
Turn the beef onto the other side and leave for 20 seconds. Add the butter and baste the meat for a further 40 seconds
  • 50g of salted butter, high-quality
8
Remove the beef from the pan and place on a tray. Pour the cooking fat from the pan over the beef and leave to rest in a warm place for 8–10 minutes
9
Meanwhile, cut each onion in half and place cut-side down onto a hot pan or plancha with a dash of oil. Once well-coloured, remove from the heat, separate each onion half into individual petals and season with salt and a little vinegar
  • red wine vinegar
10
Pour the fat and juices from the beef into a pan and add the salsa verde. Warm gently over a low heat
11
Slice the beef and arrange over warmed plates. Dress with the warm salsa verde and onion petals, then finish with some dressed watercress
  • olive oil
  • watercress
  • salt