1. Preheat oven to 375 degrees.
2. Cut spaghetti squash in half lengthwise and scoop out the seedy part.
3. Put a little olive oil on the exposed cut part and set cut side down on a baking sheet; cook in preheated oven for 35 to 45 minutes or until fork tender.
4. Remove, let cool slightly, then flip over and pull "spaghetti strands" out of squash using a fork; put spaghetti strands in a large bowl; cover to keep warm and set aside.
5. Put 2 Tbsp of the butter in a saucepan over medium heat, stirring until melted.
6. Slowly drizzle in the cream, whisking as you add and cook, stirring, for 2 to 3 minutes.
7. Add the garlic, stir, then, while stirring, start adding the cheese, continually stirring with a big spoon in a 'figure 8' until all cheese is added and blended well.
8. Add the parsley and stir.
9. Pour the cheese sauce over the warm spaghetti squash "noodles" and toss to combine. Taste for salt and season if necessary. Serve with a sprinkle of Parmesan cheese if desired.