Cook cauliflower until al dente, drain and chop into bite sized pieces.
Melt butter in a sauce pan over medium heat, add almond flour whisking constantly until combined.
Add cream to the sauce pan, mix well and bring to a boil stirring frequently. Remove from heat when the mixture begins to boil and thicken. Add salt and pepper to taste.
In a medium frying pan, saute onion and sausage over medium heat until onion is opaque.
Place cauliflower in a 9x11" baking dish. Top with onion, sausage and pour cream sauce overtop.
Sprinkle entire dish with shredded cheese and bake at 350 for 20 mins.