Preheat oven to 400 F, option to line a baking sheet with parchment paper for easy cleanup.
Slice your squash in half, and remove the seeds using a spoon. Place squash cut side down on prepared baking sheet, and bake in preheated oven until your squash shred easily with a fork, about 35 minutes. (psst--you don't want to overbake the squash, as the pasta will become mushy).
Once the squash is done cooking and cool enough to handle, flake the flesh using a fork and shred it into "spaghetti". Add it to a large bowl. Place the spaghetti squash shells back on the baking sheet, cut side up.
Add the chicken, celery, half the green onions, ranch dressing, and Frank's red hot, and toss to combine.
Fill spaghetti squash shells with combined filling. Sprinkle with shredded cheddar, and bake in oven until the cheese is melted and the filling is heated through about 10-15 minutes. Sprinkle with remaining green onions and blue cheese crumbles before serving, and enjoy!