You can always eliminate the onions from a crock pot recipe unless they are the main ingredient in the dish. Everyone has their own tastes and what is nice about recipes are you can adjust them to your tastes.
Here is a recipe for the crockpot involving spaghetti squash:
1 whole spaghetti squash (2-3 lbs)
1/2 cup water
2-4 tbsp. butter (optional)
Salt & pepper to taste (optional)
Place whole spaghetti squash along with water in crock pot. Cook on high for 2 to 2.5 hours. Carefully remove from crock pot and slice in half, lengthwise. Allow to cool slightly before removing seeds.