Preheat the oven to 400℉ and line a baking sheet with parchment paper.
Carefully cut the spaghetti squash in half lengthwise and scoop out the seeds. Brush on avocado oil to both halves and sprinkle with some salt and pepper.
Place them cut side down on the baking sheet and bake for 35-40 minutes, or until tender and can easily be shredded with a fork.
While the squash is baking, make the chicken meatballs. In a large bowl, combine the ground chicken, breadcrumbs, parmesan, egg, minced garlic, dijon mustard, maple syrup, salt, pepper, thyme, sage, and red pepper flakes. Mix until just combined.
Form the mixture into 1-inch meatballs. Add a generous drizzle of avocado oil to a large skillet over medium heat. Add the meatballs and cook for 6-8 minutes, turning occasionally, until golden on all sides.
Once browned, pour in your favorite jar of pasta sauce and gently stir to coat the meatballs. Cover and let simmer for 10-12 minutes, or until the meatballs are fully cooked through.
When the spaghetti squash is done, flip the halves over and use a fork to shred the inside into spaghetti-like strands, leaving them in the shell. Top each half with a generous scoop of the saucy chicken meatballs. Sprinkle with extra parmesan and bake again for 5-7 minutes until the cheese has melted and started to brown.
Remove from the oven, top with fresh basil, and enjoy straight from the squash "boat"!