Brush the entrecôtes with a little oil.
Charcoal/gas/electric grill: Grill the entrecôtes over/on a medium heat (approx. 200 °C for approx. 4 mins. on each side, place the entrecôtes on a board, cover and leave to rest for approx. 5 mins.
Tomato & olive salsa
Combine the balsamic with the oil, season. Add the tomatoes, olives and onion, mix. Carve the meat across the grain and serve with the salsa, season with salt.