Preheat oven to 400 degrees.
Pierce your spaghetti squash a couple times with a fork and microwave it for 4 minutes. This will make it much softer, then chop it in half and scoop out the seeds.
Microwave the two spaghetti squash halves in a shallow bowl of water for another 10 minutes to expedite the process.
While the spaghetti squash is microwaving, chop the turkey bacon into pieces and cook through all the way in a large skillet. You can also add in the chopped red onion right after and cook together.
Brush the inside of each spaghetti squash half with a little olive oil, salt and pepper. Bake for about 10 minutes.
In the skillet with turkey bacon and onions, add chicken, BBQ sauce, and cheese. Stir together until hot.
With a fork, take off the spaghetti squash strands and mix in with your BBQ sauce mixture. Stuff the spaghetti squash with the combined mixture, and top with more cheese, if desired. Bake for about 10 minutes, so everything comes together. Top with scallions and more BBQ sauce, if desired.