If you're fastidious about your pumpkin or squash being roasted unevenly and siting in the oven on a lopsided manner because of it's uneven, irregular shape and they won't stay flat and and you have a pyrex™ salad bowl or coffee cup-then your problem has just been solved: any OVEN-PROOF/heat-proof vessel will do.
A wok ring or any metal ring smaller than the vegetable works too!
It's very important that the container you have are slightly smaller than the pumpkin/squash. The idea is to have something to cradle it inside the oven and the heat evenly roasts the vegetable without the brown sugar, butter, etc spilling over the pan.
Don't forget to put at least a quarter or half of hot (NOT boiling) water in the bowl or mug.
So there you go: the most easiest way to get these vegetables in your mouth to your belly. If you just wanted the flesh : NO PEELING, NO CHOPPING required to make it into smaller pieces (you do that after you roast it). Just wash and cut in half then oil and season.