Preheat oven to 400 F. Cut spaghetti squash in half, lengthwise. Scoop out seeds and discard. Season inside with olive oil, salt and pepper. Place cut side up on a rimmed baking sheet. Bake for 1 hour.
Meanwhile, heat olive oil in a large pan over medium heat. Add the sausage and the onion, breaking the sausage apart with a spoon. Once the sausage is cooked through (the pink is gone) add the garlic and sage; cook for another 1-2 minutes. Add the wine and cook for 1 minute. Add the pumpkin puree, broth, goat cheese, cinnamon, nutmeg, salt, and pepper, stirring until fully combined. Remove from the heat to cool.
Scoop out the spaghetti squash threads and place in a large bowl. Season with salt and pepper. Add the cooled pumpkin sauce and eggs, and stir to fully combine.
Transfer mixture to a greased 9x9 baking dish. Turn down oven to 350. Bake for 1 hour or until top and edges are browned.
Recipe by Laughter and Lemonade at https://www.laughterandlemonade.com/pumpkin-sage-spaghetti-squash-casserole/