These beef and mushroom stuffed zucchini boats are a creative and delicious way to use ground beef. The ground beef is cooked with onions, garlic, and mushrooms, then mixed with breadcrumbs and cheese. The mixture is stuffed into hollowed-out zucchini halves and baked until the zucchini is tender and the filling is golden and bubbly. These zucchini boats make a satisfying and nutritious meal that is low in carbs and high in flavor.