Preheat the oven to 180c. Place the tomato passata, vinegar, sugar and mustard in a pan. Bring to a simmer then add the seasoning. Take off the heat and pour in the chicken and spring onions. Stir together.
Take a wrap and fill the middle with cheese then put a spoonful of the chicken on either side. Roll up so that the cheese is in the centre then lie in a baking dish. Repeat until the dish is full then brush with the melted butter.
Bake for 15 minutes or until the tortillas are crisp and golden brown. Serve up with soured cream or rice.