Preheat the oven to 350F/180C and lightly grease a casserole dish.
Place the cauliflower in to the casserole dish, drizzle with the olive oil and stir, sprinkle the sea salt and black pepper evenly.
Bake for 15-20 minutes, and stir halfway through.
Add the shredded chicken and 1 cup of the shredded mozzerella cheese, mix well.
In a bowl mix the basil pesto an dthe heavy cream, pour over the casserole and stir until fully mixed, sprinkle the remaining shreedded mozerella cheese evenly over the casserole.
Place back in the oven for 10-15 minutes until the cheese is melted then add the shredded fresh basil leaves before serving.