Pluck the parsley leaves from the stalks, wash and dab dry. Chop parsley finely. Wash lamb's lettuce, spin dry and clean. Heat the oil in a pan and fry the steaks for 2-3 minutes while turning.
Cut Brie into 8 slices. Cover steaks with brie and put them on a baking tray. Melt in the preheated oven (electric cooker: 225 °C/ circulating air: 200 °C/ gas: level 4) for about 3 minutes. Toast the bread, spread with 1 teaspoon of butter on each and cover with steaks and salad.
Arrange toasts on plates and serve with mango chutney. Sprinkle with parsley.