One thing that can go wrong with baked whole pumpkins is incinerating it into mush. Filled with cream and Gruyère cheese, you’ll know when the pumpkin is overcooked. It will likely collapse into a deflated mound of white and orange laced with strings of melted Gruyère. The semi-successful dish will still be delicious, as long as the cream spills into a baking dish instead of the oven floor.
That’s my long-winded way of saying that you can’t mess this non-recipe up.
The pumpkin top is sliced off to serve as its own lid and the structural integrity of the baked pumpkin depends on the carving method. Instead of cutting off the tops horizontally in one stroke, use a narrow pointed knife and slice around the stem at a 45 degree angle. Just don’t forget to watch those fingers.