Preheat oven to 375F. Grease baking dish or line with aluminum foil. Halve squash lengthwise and remove seeds and strings. Arrange cut side up in baking dish and brush lightly with olive oil. Cover with foil and bake until tender, about 45 min to 1 hour. Remove from oven and let squash cool before handling. Scoop out most of the flesh.

Heat a large skillet over med-high heat and cook turkey, about 8-10 min, breaking it up with a wooden spoon to avoid oversized clumps. Remove turkey from skillet, then wipe down skillet with a paper towel. Add butter and cook onion, celery, and apple until tender. In a large mixing bowl, add turkey, veggies, cornbread stuffing, scooped out butternut squash, chicken broth, and eggs. Mix until well incorporated.

Add stuffing to hollowed out squash and top with generous amounts of parmesan. Bake uncovered until stuffing is cooked through and cheese has melted, approx 15-20 min.