Meatball Stuffed Spaghetti Squash

Preheat the oven to 400° with two racks in. Cut spaghetti squash in half lengthwise and scoop out seeds. Drizzle with 2 tablespoons of the olive oil and season with salt and pepper. Place cut side down on a large baking sheet and roast on the bottom rack until it shreds easily, about 40 minutes.

Meanwhile, make the meatballs: Grease a large baking sheet with cooking spray. In a large bowl, combine beef with bread crumbs, parsley, parmesan, egg, 1 minced garlic clove, 1 teaspoon salt, and a few pinches of red pepper flakes. Roll mixture into 16 meatballs and place on prepared baking sheet. Bake on the upper rack, until golden and cooked through, about 15 minutes.

While the meatballs and squash are baking, heat the remaining 2 tablespoons of oil over medium-high in a large skillet. Add onion and cook, stirring, until soft, about 5 minutes. Add the remaining garlic and cook, stirring, until fragrant, about 30 seconds. Pour in the crushed tomatoes and add a few pinches of red pepper flakes. Simmer until sauce has thickened, about 10 minutes. Season with salt and pepper.

Heat broiler on high. Shred spaghetti squash into strands with a fork. Spoon meatballs and sauce into squash. Stir and top with mozzarella cheese. Broil until golden.

Garnish with basil and serve.