Preheat the grill function on the oven.
In a medium saucepan, sauté onion then add the chicken strips and cook until well browned in the oil, for 2 minutes.
Add the 800 ml milk and uncooked pasta and add the sachet of Seasoning Spice Blend. Bring to the boil, stirring occasionally. Reduce the heat and allow to simmer uncovered for 10 - 15 minutes, stirring occasionally until the pasta is cooked.
Blanche the broccoli for 2 minutes in rapidly, boiling water seasoned with salt. Drain and roughly chop.
Empty the contents of the Cheese Sauce sachet into a measuring jug and fill to 200 ml with rapidly boiling water. Once all the water has been added, stir with a fork for 1 minute, until thick and smooth then set aside.
Fold the broccoli and pesto through the pasta in the saucepan.
Remove the pan from heat and pour into a 2L oven proof dish. Pour the cheese sauce over and top with grated cheese.
Grill for 10 minutes or until cheese is golden brown.