Use a sharp knife to remove the tops from each pumpkin (like a jacko’-lantern). Scrape out the seeds and filaments and discard. Season the inside of the pumpkins with salt and pepper.
Melt butter in a large skillet over medium heat. Add the onion and sauté for 5 minutes or until limp. Add sausage and cook until lightly browned, then add the garlic and apples and cook 2 minutes more. Remove from heat.
In a medium bowl, combine the onion and sausage mixture with the stuffing mix, cheese and broth and mix together until combined and slightly moistened.
Divide and lightly pack the stuffing into the pumpkins until completely full. Replace the tops on the pumpkins, place them on a lined or lightly-oiled baking sheet or dish and into the oven.
Depending on the size of the pumpkin and amount of flesh, the pumpkins should take about an hour to bake. Check after 30 minutes and, when nearly cooked, remove the tops and bake until the filling is browned. The pumpkins are done when easily pierced with a knife.
Use two metal spatulas to move them from the baking dish onto the serving platter, to help keep the pumpkins intact. To serve, slice pumpkins into wedges or halves.