Steak Burger with Truffle Cheese and Roasted Onions

Sophie Grigson dresses-up burgers with top-quality beef, Italian cheese and meltingly soft roasted onions
By Sophie Grigson
Steak Burger with Truffle Cheese and Roasted Onions
  • Rating:
  • Serves: makes 2 generous-sized burgers, or 4 smaller ones
  • Cook Time:
  • Prep Time: 25 minutes
  • Effort: easy


For the onions

  • 4 small onions, (each about 115g)
  • 3 tbsp olive oil
  • 3 tbsp balsamic vinegar, or sherry vinegar
  • salt and black pepper

For the burgers

  • 2 x 260 g chunky sirloin steaks
  • 2 shallots, very finely chopped
  • 2 tinned anchovy fillets, finely chopped
  • 2 tbsp chopped parsley, heaped
  • pepper

For assembling the burgers

  • 8 sweet cherry tomatoes, sliced
  • 4 slices truffle cheese
  • 2-4 soft rolls, or ciabatta style rolls
  • 2 baby gem lettuce, shredded


1. For the roasted onions, preheat the oven to 180C/gas 4. Slice the root off each onion, cutting close to the base so that the onion holds together. Slice the top off, peel away the skin, and cut each onion into 8 wedges, without cutting right through to the base - stop cutting about 1 cm from the root end.

2. Place the onions, root end down, in an oiled roasting tin, leaving plenty of space between each one so that the 'petals' can open out. Drizzle a little olive oil over and season with salt and pepper. Roast for 30-45 minutes, until tender. After about 20 minutes, baste with its juices and drizzle over the vinegar. Return to the oven and continue cooking. Serve hot or warm.

3. For the burgers, cut off and discard the firm band of fat located around the edge of each steak. Don't remove every last piece of fat though - some fat is essential for flavour and moisture.

4. Slice the steak thin strips, and cut each strip into very small pieces. Tip the meat into a mixing bowl and add the shallots, anchovies, parsley and pepper.

5. Combine all these ingredients with your hands, and divide into 2 large portions, or 4 smaller ones. Shape each portion into a plump burger.

6. Preheat the grill for 10 minutes. When it's really hot, place the burgers 8-10 cm from the heat, and grill until golden. For smaller, thinner burgers, allow about 5 minutes on each side for medium rare, but increase the time to make more well-cooked burgers.

7. To assemble the burgers, divide the sliced tomatoes between each cooked burger, and cover with a slice of truffle cheese. Place under the grill for a few more minutes, until the cheese softens.

8. Cut the bread rolls in half horizontally and heap a portion of lettuce on the base of each one. Lay a burger on top, replace the lid and serve straight away with the roast onions.

Rate This Recipe