Rump Steak and Caramelised Onion Sandwiches

Marinade: Combine the ingredients in a shallow dish or zip lock bag and add the steak, turning to coat. Marinate for at least 1 hour or refrigerate for up to 24 hours.

Caramelised onions: Heat the oil and butter in a sauté pan. Add the onions, season, cover and cook for 10 minutes. Uncover and stir in the garlic, balsamic vinegar and brown sugar and cook, uncovered, for a further 20 minutes, stirring to prevent them sticking. Remove and set aside.

Combine the mayonnaise, basil and lemon juice in a small bowl.

Heat a sauté pan or barbecue until hot and grill the bread on both sides. Remove the steak from the marinade and pat dry. Season generously with sea salt and cook for about 4 minutes each side for medium rare. Cooking time will depend on the thickness of the steak. Remove to a plate, cover loosely and rest for 10 minutes.

Slice the steak very thinly across the grain.

Spread one side of the grilled bread with basil mayonnaise, then top with rocket, tomato, steak and the onions.