Carefully place each half on cookie sheet, give exterior skin a nice olive oil rubdown - and salt/peppering. Pour about a 1/4 inch of water in the cookie sheet. This will add a bit of steam to the roasting process & keep your squash from drying out. (Can you see the bit of water in this pic?)
Place in 400 degree oven for about an hour. You should check in every now and then to see if you need to add more water. This is the look that you're going for - just roasty enough on the outside, a weensy bit caramelly on the pan and easily pierced by a knife. You'll love how the fragrance that this process creates will fill your kitchen.
Let cool a bit (& remove rosemary sprigs - they are quite pungent & have already added quite a bit of flavor) before scooping out the flesh. If you've properly babysat the water at the bottom of the pan & it hasn't burned too much - pour the caramelly roasting juices in with the scooped out squash-flesh.
Salt - Pepper - Butter to taste. Enjoy!
