Cut spaghetti squashes in half and place them face down on a baking sheet lined with parchment paper.
Put whole chicken breasts on a baking sheet lined with parchment paper.
Roast both spaghetti squashes and chicken in the oven for 30 minutes.
Meanwhile, blend all remaining sauce ingredients in your blender or food processor until smooth - roughly 2 to 3 minutes
Because the sauce isn’t heated, you can throw the sauce into a pot to warm it up slightly if you want to. Alternatively, when you mix it into the hot spaghetti squash and chicken, it will warm it up.
Scrape out the cooked spaghetti squash into a large bowl and pour the sauce on top and mix thoroughly.
Serve with sliced up roasted chicken breast and chives for garnish if desired.