Preheat toaster oven to 350 degrees F (175 degrees C).
Place spaghetti squash halves on a compact baking sheet. Place 5 pieces of butter into each half. Sprinkle 2 tablespoons brown sugar and 1 tablespoon cinnamon over each half.
Bake in the preheated oven until soft, about 1 hour.
Remove squash from oven and scrape insides with a fork into a loose pile of strands.
Return to the oven and bake until flavors combine, about 10 minutes more. Let cool before serving, about 10 minutes.
