1. Season the fillets with salt and pepper. Heat a pan over the heat and add the olive oil. When hot, add the fillets and sear them briefly on both sides.
2. Add one tablespoon of butter and the thyme. Let the fillets brown nicely and remove them from the pan. Place them on a plate and cover them to keep warm.
3. Add the onion to the same pan and sauté for 1 minute. Add the mushrooms and garlic and sauté over high heat for 2-3 minutes. Remove them from the pan and keep them warm. In the same pan, add the remaining butter (one tablespoon) and stir until melted. Pour in the chicken stock, balsamic reduction, heavy cream, and grated Halloumi. Stir and return the meat and mushrooms to the pan. Lower the heat and simmer for 2-3 minutes. Turn the meat and continue simmering until the sauce thickens.
