Mix tartar sauce, yoghurt and mustard. Cut the baguette open lengthwise. Spread half of the tartar sauce on top. Wash and slice the tomatoes and cucumber. Clean and wash the lettuce, dab dry and pluck into small pieces.
Cover the baguette with prepared ingredients and turkey breast cold cuts. Spread the rest of the tartar sauce on top. Sprinkle with fried onions and place the other half of the baguette on top. Makes about 6 pieces.