Preheat oven to 400° and line a 13x9 with parchment paper.
Place cooked spaghetti squash in a large bowl and pat dry with paper towel.
Cut bacon with scissors and place in a large skillet.
Cook on medium/high until crispy. Remove half onto a plate and add onion and chicken to remaining bacon.
Cook until onion is tender and chicken is cooked through.
Add chicken mixture to the spaghetti squash and then add the barbecue sauce. Start with 1 1/2 cups and add more if needed. Add the pepper, salt if needed, and garlic powder. Stir until everything is mixed well.
Add the eggs, stirring completely.
Place mixture into prepared pan, top with remaining bacon and bake 30-35 minutes.