Acorn Squash 1 medium acorn squash, halved and seeded 1 tablespoon butter 2 tablespoons brown sugar Preheat oven to 350 degrees F (175 degrees C). Turn acorn squash upside down onto a cookie sheet. Bake in a 350 degrees F (175 degrees C) oven until it begins to soften, approximately 30 to 45 minutes. Remove squash from the oven and turn onto a plate so that the flesh is facing upwards. Place butter and brown sugar into the squash, and place remaining squash over the other piece. Place squash in a baking dish (so the squash won't slide around too much) while baking. Place squash in the 350 degrees F (175 degrees C) oven and bake another 30 minutes. Back to Dinner Recipes