Chef's Recipes

Luca's corned beef buns with horseradish, parmesan and walnut sauce

The classic English corned beef bun is taken to another level by London's Luca restaurant with a walnut, parmesan and horseradish sauce.

By Isaac McHale
  • 30 mins preparation
  • 20 mins cooking
  • Serves 4
  • Print
"Even if you never make this sandwich, you want to know about this sauce: a beautiful mild, bitter sauce showing the subtler side of walnuts," says Luca chef Isaac McHale.
"It's a bit of an Italian classic and it reminds me of the background flavours of parmesan; a tiny bit of cooked garlic, olive oil and a little horseradish tie it all together. It's a great sauce for bollito misto or as an alternative sauce for vitello tonnato, or just something to serve with cold roast pork, lamb or beef the day after a big roast."
At Luca, McHale serves these rolls with brined ox tongue; we've used corned beef.


  • 4 white rosetta or other white bread rolls
  • 400 gm cooked corned beef (or brined ox tongue), thinly sliced
  • Freshly grated horseradish, to serve
  • Bitter leaves and gherkins (optional), to serve
Walnut sauce
  • ½ garlic clove, thinly sliced
  • 1 tbsp olive oil
  • 20 gm crustless day-old sourdough
  • 1½ tbsp milk
  • 100 gm walnuts
  • 35 gm parmesan, finely grated


  • 1
    For walnut sauce, place garlic and oil in a small saucepan over low heat until just warm, then cool. Tear up the bread and soak in a bowl with the milk (10 minutes). Place walnuts in a saucepan of cold water, bring to the boil, then immediately drain and repeat twice. Blend blanched walnuts, soaked bread, parmesan and a pinch of salt in a blender until smooth, then add garlic, oil and enough water to form a thick sauce (about 100ml-140ml). Season to taste.
  • 2
    Preheat oven to 160C. Place bread rolls on an oven tray and warm in oven (5-6 minutes). Cool rolls briefly, then cut in half, spread with a small amount of walnut sauce and layer in lots and lots of slices of corned beef. Occasionally season a layer with freshly grated horseradish and a turn of pepper. When the sandwich is filled and the top layer of beef is nice and flat so the sauce won’t run off, spoon 2 tbsp walnut sauce over beef. Put the top half of the roll on and gently press (McHale secures his with 2 skewers and serves them cut in half). Serve with lots of napkins, a salad of bitter leaves and a quarter gherkin each.


Drink Suggestion: A Negroni! Drink suggestion by Johnny Smith