Preheat oven to 350 degrees.
Cut the zucchinis in half and scoop some of the flesh out being careful to not make the shell too thin.
Coarsely chop the mushrooms
Heat olive oil in a skillet over medium heat. Add garlic and onion and cook until translucent.
Mix in mushrooms and the flesh of the zucchini and cook for 2 minutes. Season with salt and pepper and incorporate cream cheese. Remove from the heat.
Fill the zucchini boats with the mushroom stuffing. Cover with mozzarella cheese and top with Parmesan cheese.
Place in an oven proof baking dish and bake uncovered for 25 minutes. The filling will be nice and hot, the zucchini boat will be tender and the cheese melted and delicious!