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Recipe: Roast beef open sandwich and caramelised onion, wholegrain mustard & pickles

Make the most of your favourite cut of beef with this easy recipe from Spier

By House & Garden South Africa | October 22, 2021 | Recipes

Spier shared their recipe for a roast beef open sandwich and caramelised onion, wholegrain mustard & pickles that is perfectly paired with their Signature Cabernet Sauvignon.

While your meat is roasting, round up the other ingredients for assembling sandwiches in a flash. Be generous with all of the toppings, especially the mustard sour cream.

Ingredients (Serves 4)

At least 500g boneless beef roast (silverside or brisket)

30ml (2 tablespoons) Dijon mustard

Salt and pepper to taste

45ml (3 tablespoons) olive oil

3 onions, halved and thinly sliced

1 sprig of chopped rosemary, leaves only (discard woody stalk)

45ml (3 tablespoons) brown sugar

45ml (3 tablespoons) balsamic vinegar

4-8 thick slices of sourdough bread

Butter, for spreading

1/2 cup thick sour cream

45ml (3 tablespoons) wholegrain mustard

A few sliced sweet and sour pickled gherkins

A small bunch of rocket leaves for topping


For the beef roast

Preheat the oven to 180°C. Place the beef on a sheet of foil on top of a roasting tray, then rub it all over with Dijon mustard and season with salt and pepper. Close the foil around the beef (wrap it up), then roast 30 minutes per 500g of meat (30 minutes for 500g, 45 minutes for 750g, 1 hour for 1kg). Remove from the oven, open the foil and leave to cool.

For the caramelised onions

While the beef is roasting, caramelise the onions until completely soft in a wide pan with oil and rosemary over medium heat (at least 15 minutes). Add sugar and balsamic, then turn up the heat and stir, simmering until the sugar melts and the onions caramelise. Remove from the heat and set aside to cool, then slice thinly using a sharp knife or meat shaver.

To assemble: Butter the bread and thickly spread the sour cream and wholegrain mustard mix. Top with thinly sliced meat, pickles, caramelised onion and rocket. Serve warm or at room temperature.