Heat your oil and butter in a large skillet over medium heat.
Add the onion and saute until soft. Stir in the cauliflower rice and garlic.
Cook stirring frequently until the cauliflower rice is just tender, around 6-8 minutes.
Meanwhile, in a medium bowl, whisk your milk and flour together until smooth.
Season the cauliflower with sea salt and pepper to your taste.
Pour in the milk mixture and cook, stirring continuously until the sauce thickens.
Stir in the parmesan cheese and fresh thyme leaves, then remove from the heat.
Garnish with a few more fresh thyme leaves and a pinch of freshly grated parmesan cheese if desired.
Serve immediately and enjoy!