Grilled Garlic Pepper Flank Steak

Ingredients

• 1/4 cup (2 fl oz or 60 ml) red wine vinegar
• 2 tablespoons (1 fl oz or 30 ml) olive oil
• 1 tablespoon (10 g) coarsely ground black pepper
• 1 tablespoon (10 g) garlic, minced
• 1/2 teaspoon (1 g) ground coriander
• 2.2 lbs. (1 kg) flank steak
• salt and freshly ground black pepper