Open Beef Sammies with Caramelised Onions and Béarnaise Sauce

A quick and delicious midweek meal.

My Gluten-Free Food Bag
Open Beef Sammies with Caramelised Onions and Béarnaise Sauce

This dish most recently appeared in My Gluten-Free Food Bag on Sunday, April 30, 2017.


  • 400g potatoes, scrubbed and diced 2cm


  • 1 brown onion
  • 2 tablespoons GF balsamic vinegar
  • 1 tablespoon brown sugar


  • 550g beef rump steaks (at room temperature)
  • 1 tomato
  • ½ telegraph cucumber *
  • ½ bag mesclun leaves *
  • 2 teaspoons olive oil
  • 1 teaspoon GF vinegar (e.g. red wine, white wine, cider)


  • 1 GF rosemary flattie
  • 80g Béarnaise sauce (at room temperature)
  • PREHEAT oven to 220°C. Line an oven tray with baking paper.
  • 1 Toss roasties on prepared tray with a drizzle of oil and season with salt and pepper. Bake for about 25 minutes, until golden and tender. Turn once during cooking. While roasties are cooking, heat a drizzle of olive oil in a small pot on medium heat.
  • 2 While oil is heating, slice onion very thinly. Cook onion, stirring often, for about 5 minutes, until soft and starting to colour. Add vinegar and sugar, stir, reduce heat to low-medium and simmer for about 10 minutes, until thick and glossy. Stir often to avoid burning.
  • 3 Pat beef dry with paper towels and season with salt and pepper. Heat a drizzle of oil in a large fry-pan on medium-high heat. Cook beef for about 2 minutes each side for mediumrare (depending on thickness), or until cooked to your liking. Set aside, covered in foil, to rest for 5 minutes.
  • 4 When roasties have 10 minutes cook time remaining, cut flattie into 2-3 pieces widthways, then carefully slice horizontally through the middle. Push roasties to one side of the tray and place flattie, cut-sides facing up, on other side of tray.
  • 5 Return tray to oven to bake for final 8 minutes of cook time (for roasties), until flattie is lightly toasted. Thinly slice tomato and cucumber and add to a large bowl with mesclun, oil and vinegar. Toss to combine and season with salt and pepper. Slice beef thinly against the grain.
  • TO SERVE top a piece of rosemary flattie with caramelised onions, slices of beef and a good drizzle of béarnaise sauce. Divide open beef sammies, salad and roasties between plates.
  • SERVES 4-5

Nutritional Information

  • Energy: 2580 kj / 617 kcal
  • Protein: 31.6g
  • Carbohydrate: 53.1g
  • Fat: 30.1g


  • Pantry staple
  • * Shared ingredient with another recipe

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