Slicing the beef in the Italian ''tagliata'' style makes it go further but if your guests are big eaters, you might want the insurance of three steaks rather than two.
800g all-purpose potatoes, peeled
250g goose fat
1/2 red onion, sliced
8 garlic cloves, unpeeled but squashed
2 twigs rosemary
Sea salt and pepper
2 thick rib eye steaks, 300g each
2 tbsp olive oil
75g rocket leaves
Cut potatoes into 1.5-centimetre cubes. Melt goose fat in a fry pan or divide between two pans; the potatoes should form one layer. Add potatoes, red onion, garlic cloves and rosemary. Cook over gentle heat, moving the potatoes around, for 20 minutes, then raise heat to medium and cook for 10 minutes until golden brown.
Take out onion when it's crisp and garlic cloves when soft inside. Drain potatoes on paper towel, then toss with sea salt and keep warm.
Heat barbecue to medium and remove beef from fridge for 20 minutes before grilling. Brush both sides with olive oil, season well and grill for seven minutes on the presentation side until well-browned, then turn and cook for four minutes on the other side, or to your liking. Rest in a warm place for 10 minutes, then thickly slice beef at a 45 degree angle.
Arrange slices in a single layer on a large warm plate or on individual warm dinner plates. Strew with sea salt, pepper, roast potatoes, garlic cloves and rocket leaves. Drizzle with a little extra virgin olive oil and serve immediately.