Coat the potato wedges with 1tbsp of oil, then spread onto a baking sheet. Bake the wedges in a preheated oven 200°C, 180°C fan, Gas 6 for 30 minutes, turning regularly until browned.
Meanwhile, place the turkey steaks under the grill on a low-medium heat. Grill for about 20 minutes or until the steaks are cooked through with no pink showing.
Mix the avocado, tomatoes, watercress and yogurt together to form a guacamole, then season.
Sprinkle each side of the turkey with chilli, add to a large pan with the rest if the oil and cook for 3 minutes on each side. Cut the baps into halves and spread the guacamole onto each half. Add a turkey breast and a lettuce leaf and serve with potato wedges.
Turkey is low in fat and high in protein. Avocados are rich in cholesterol-lowering monounsaturates and sweet potatoes are a good source of betacarotene. Watercress provides calcium and iron.
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For top tips on protecting you and your family when preparing raw meat and poultry, visit Food Safety in the Home.