Cut the acorn squash in half. Scoop the seeds out with a spoon and discard.
Rub olive oil, salt, and pepper on the inside of the squash.
Place the squash cut side down on a medium size baking sheet. Place in the oven and cook for 45 minutes or until the inside is fork-tender.
Remove from the oven, flip over, and add butter and brown sugar into the center of the squash, where the seeds used to be. Let the butter and sugar melt for about 2 minutes.
With a fork, lightly mix the butter and sugar into the squash.
Scoop the insides of the squash out with a spoon and serve or place the entire half on a plate and eat directly out of it!