Preheat oven to 350°F.
Cut spaghetti squash lengthwise and place, cavity side down on oiled baking sheet.
Roast for 45-60 minutes or until cooked throughly and "spaghetti" is easily removable. Set aside.
Heat butter and olive oil in a large skillet.
Add onions and cook until translucent, about 4 minutes.
Infuse the sauce.
Add cream, parm, chives and basil. Simmer for a few minutes to heat through.
Plate spaghetti squash in shallow bowl.
Pour sauce over spaghetti and devour immediately.