Preheat oven to 450°F. Line a baking sheet with parchment paper and lightly spray with nonstick cooking spray.
Rinse the outside of the acorn squash and cut in half. Scoop out the seeds and place squash face up on the baking sheet. Lightly brush with oil and season with salt and pepper. Bake squash for 25-30 minutes or until fork tender.
While your squash are baking, heat 1 tablespoon of oil in a skillet over medium high heat. Add onion, celery and apple and saute until softened. This will take about 10 minutes. Add garlic and sage towards the last few minutes.
Add the sausage to your pan and cook until browned, breaking it up into small pieces. Once the sausage is brown, add chicken broth and stir to combine. Cook for a few more minutes until the chicken broth has soaked into the mixture. Remove from heat and stir in cranberries.
When the acorn squash is done baking, remove from the oven and fill each squash with the sausage/veggie mixture. You can sprinkle your choice of cheese on top and bake for an additional 5 minutes to melt the cheese if you want! Serve warm and enjoy.