Slice the spaghetti squash in half (the long way) and scoop out the seeds. Either place both halves in cut side down (if they’ll fit that way), or place both in the crockpot on their sides (like an oyster shell).
Mix all ingredients for the meatballs in a bowl. Roll into meatballs and place in crockpot around the squash (or, if you have it oyster-style, place the meatballs in the squash).
Mix all ingredients for the sauce except fresh basil, and pour into crockpot, coating the meatballs and squash.
Cook on high for 3-4 hours or on low for 6-7 hours.
When it’s ready, remove the spaghetti squash from the sauce and meatball mixture. Place on a cutting board or plate. Use a fork to pull out the squash noodles from the inside, and discard the outer portion of the squash.
Meanwhile, add fresh torn basil leaves and cook with the sauce and meatballs for about 5 more minutes. If the sauce is thin, keep the heat on high and let it sit uncovered for 30 minutes before serving – it should thicken up a bit.
Top the spaghetti squash with sauce and meatballs. Serve & enjoy!