Beef sirloin with mushroom sauce

Ingredients

• - Beef sirloin 4 pieces of 350 g
• - Olive oil, 40 ml
• - Salt and ground black pepper
• - Maldon sea salt
• - Butter, 60 g
• - Shallots, 100 g
• - Peeled garlic, 2 units.
• - Seasonal mushrooms
• - Port wine, 400 ml
• - Dark beef broth, 600 ml
• - Starch, cornflour, etc.
• - Salt and sugar