Place a pan of water on high heat, and boil the broccoli until al dente. Drain well and add to a large mixing bowl along with the shredded chicken.
In a small saucepan, add the cream cheese, heavy cream, almond milk, mustard, garlic, salt and pepper and place it on a low heat. Whisk until the sauce is smooth.
Pour the warm sauce into the broccoli and chicken mixture, add the basil and mix well.
Pour the mixture into a casserole dish and top with the grated cheese.
Bake in the oven for 20 - 30 minutes, until warmed through and the cheese is melted and golden.