Preheat oven to 400 degrees Fahrenheit. Place chicken on a baking sheet. Drizzle with avocado oil and sprinkle with salt and pepper. Roast until done (about 20-25 minutes for chicken thighs, 35 minutes for chicken breasts). Remove and set aside. Increase oven temperature to 450 degrees Fahrenheit.
While the chicken is roasting, cut the spaghetti squash in half cross-wise. Cut the stem off, if needed for the spaghetti squash to balance. Use a spoon to remove the seeds from the center. Place the spaghetti squash on a pan, cut side up. Roast for about 40 minutes. Remove and set aside.
While the spaghetti squash is roasting, chop the bacon crosswise into ½ inch pieces and cook on medium-low heat until browned. Use a slotted spoon to remove the bacon from the pan and set aside. The bacon should have produced about 3 tablespoons of bacon fat. Keep it! Add avocado oil, if needed, to make the total oil 3 tablespoons.
Use a fork to remove the spaghetti squash from the skin and place in a large bowl. Pour the bacon fat/oil over the spaghetti squash, followed by the buffalo sauce. Use tongs or salad hands to mix well. Add salt, if needed (this will depend on the amount of salt in the bacon and buffalo sauce, and your preference).
Use tongs or forks to serve the spaghetti squash. Slice the cooked chicken and place on top. Sprinkle with cooked bacon pieces, blue cheese and scallions.
If not serving with chicken thighs, drizzle wing sauce over the finished spaghetti squash dish and serve.