Tuna steaks with a balsamic vinegar glaze

• 2 tablespoons olive oil
• 60 g pancetta, chopped
• 1 medium

Heat 1 tablespoon of oil in a heavy frying pan and sauté the pancetta until it colours lightly and the fat runs. Add the onion and cook gently for 8–10 minutes until it is soft and lightly browned. Transfer to a serving plate and keep warm. Wipe out the pan and put in the remaining tab