Preheat the oven to 350 degrees.

Slice the zucchini in half lengthwise and scoop the flesh out from the center. Reserve 1 cup of the removed zucchini flesh.

Melt 2 tbsp of butter in a skillet over medium heat on the stove and add the onions. Saute for a few minutes until beginning to soften.

Add the zucchini flesh and spinach to the skillet with the onion and saute until the spinach is wilted. Remove the mixture and set aside.

In the same skillet, add the remaining butter and the garlic. Saute for 30 seconds.

Pour the chicken broth and heavy whipping cream into the skillet and whisk to combine well. Bring the mixture to a low boil until it starts to thicken.

Season with nutmeg, salt, and pepper to taste.

Mix in the parmesan cheese and remove the sauce to set aside.

In a bowl, combine the sauce and vegetable mixture.

Add in the bacon and stir until combined.

Place the zucchini in an ovenproof skillet or casserole dish, and stuff with the filling mixture.

Sprinkle mozzarella cheese on top and bake for 15-20 minutes.

Serve with chopped parsley for garnish.