To roast the squash:

1. Preheat oven to 350°F.
2. Line a baking sheet with parchment paper and set aside.
3. Slice both ends from squash and discard. Stand squash up on one of its cut ends and use a large knife to cut the squash in half lengthwise. Scoop seeds and stringy insides out using a large spoon. Place squash cut-side down on the baking sheet.
4. Bake for 30-40 minutes or until squash is tender. Baking time will depend on the size of your squash (larger squash requiring a longer cook time). When squash is tender, allow to it cool slightly before using a fork to gently scrape the squash flesh into a large bowl. Reserve the squash shells.
5. While squash is roasting, cook the chicken.

To cook the chicken:

1. Directions for Instant Pot: Insert the rack into the inner pot. Add 1 cup water or broth. Lay the chicken on the rack. Secure lid and select ‘Poultry’ setting and increase time to 17 minutes (19 minutes if the breasts are really thick). At the end of the cooking time, allow pressure to naturally release for 5 minutes then flip the vent valve and release any remaining pressure. Move chicken to a cutting board to cool slightly before shredding with two forks.
2. Directions for Stovetop: Place a medium skillet over medium-high heat. Add 1 teaspoon avocado oil, olive oil, or coconut oil and swirl the pan to coat with the oil. Add chicken and ½ cup water. Once the water begins to simmer, reduce heat and cover. Cook chicken for 15-18 minutes or until cooked through. Move chicken to a cutting board to cool slightly before shredding with two forks.

To assemble the stuffed squash:

1. In a large bowl, place squash shreds, shredded chicken, celery, green onions, bell pepper, and buffalo sauce. Toss until well mixed and coated. Spoon the squash-chicken mixture into the reserved squash shells. Place the stuffed shells on the baking sheet and bake in 350°F oven for 10-15 minutes or until heated through.
2. Serve drizzled with ranch dressing and top with crumbled blue cheese, if desired.