Preheat the oven to 375F. Halve the carnival squash, scoop out the seeds and fibers, then cut each half into two chunks.
Place them skin-down on a shallow baking tray. Sprinkle salt and black pepper on the flesh.
Dice the bacon and combine with olive oil, rosemary, garlic, nutmeg and sugar in a bowl. Spoon the mixture over the squash chunks.
Bake on a middle rack for 25-30 minutes. Serve hot.