Cook the spaghetti squash and chicken. I used my Instant Pot. I cooked the squash for 15 minutes on manual with the vent sealed and then did a slow pressure release. Then I cooked the chicken for 8 minutes. I didn't bother washing the pot in between.
Preheat the oven to 400.
In a blender combine all the ingredients for the sauce. Blend until smooth.
Spray a 9 x 13 casserole dish with cooking spray. Put the cooked spaghetti squash in the casserole dish. Pour on half of the sauce. Put the chicken on top of that. Pour on the rest of the sauce. Sprinkle the cheese on top.