Preheat oven to 400 degrees F.
Make & bake the Fat Head pizza crust, according to THESE directions.
In a small saucepan on the stove, brown the butter and garlic for a couple minutes, while stirring on medium heat.
Whisk in cream and heat until almost boiling.
Reduce heat and whisk in Xanthan Gum.
Stir until thickened.
Add salt, pepper, and nutmeg.
Pour cream sauce over the top of pizza crust.
Top pizza with chicken, spinach, and cheeses.
Bake in the oven at 400 degrees for 5-10 minutes until cheese is melted.
Makes about 6 slices.