Preheat a medium grill. Generously season the steak with salt and pepper - leave to sit for approx 30 minutes.
STEP 2 - Mushrooms
Heat a sauté pan over medium high heat. Add the olive oil and mushrooms - sauté for 5-10 minutes until the mushrooms have caramelized. Add the shallots and sauté for 1-2 minutes. Followed by the garlic and thyme.
STEP 3 - Steak
Place the seasoned meat onto the hot grill, turning periodically to evenly cook.
Use an instant-read thermometer to check for a temp of 130 °F (approx. medium rare). Transfer to a platter, tent with foil to keep hot and let rest for 10 minutes.
Slice the steak against the grain. Top with the sautéed mushrooms and spoon any leftover steak or mushroom juices over the dish.