Add the chopped bacon to a large skillet or wok and heat over medium-high. Cook, stirring occasionally, until all the bacon pieces are nice and crispy. Use a slotted spoon to remove the crispy bacon from the skillet, leaving the fat behind.

Keeping the heat at medium-high, add the chopped onion to the skillet. Cook the onion just until it becomes nice and fragrant, about 1 minutes, before adding all of the chopped brussel sprouts and garlic. Stir well, and cover the skillet. Cook, stirring occasionally, until brussel sprouts and onion have softened, about 10 to 12 minutes.

Preheat the oven to 400 degrees F.

Transfer the brussel sprouts and onions to a large casserole dish.

Place the skillet back on the stove top (still on medium-high heat) and add the can of full-fat coconut milk. Bring the coconut milk to a full boil, then whisk in the gluten-free all-purpose flour (or regular all-purpose flour). Add about ½ teaspoon sea salt and ¼ tsp black pepper (salt the sauce to taste) and the nutmeg if desired. Continue whisking constantly at a full boil until the mixture is very thick. Remove from the heat and stir in the grated cheese until melted.

Pour the sauce mixture over the brussel sprouts and stir well until everything is well coated.

Add the almond flour to a larger measuring cup or bowl, add a sprinkle of sea salt along with 2 tablespoons of avocado oil. Stir the mixture together well so that the almond flour is lightly coated in oil.

Sprinkle the cooked bacon and almond flour over the casserole. Bake on the center rack of the preheated oven for 12 to 18 minutes (I keep mine in for 15), until the sauce is bubbly and the topping is golden-brown. Serve immediately, and enjoy!