Place the squash, cut side up, on a damp paper towel in a microwavable dish. Microwave on high until tender, about 15 minutes. Using a fork, scrape the strands of squash into a microwavable bowl and toss with the butter and 1 tablespoon olive oil. Season to taste with salt and pepper.
Meanwhile, combine the sausage with the bread crumbs and form into 1-inch meatballs. In a large skillet, heat the remaining 1 tablespoon olive oil over medium-high heat. Add the meatballs and cook, stirring, until browned, about 6 minutes. Cover and cook over low heat until cooked through, about 3 minutes more.
Reheat the shredded squash in the microwave and top with the meatballs, cheese and basil.