Sweet-recipes-in-microwave-oven, lay cut side down on a piece of microwave safe plastic wrap placed directly on microwave bottom or plate. cook on high in 5 minute intervals until completely softened and cooked through, about 5 to.... Place squash cut side down in a microwave-safe dish. cover and microwave on high for 10-12 minutes or until tender. turn squash cut side up. fill centers of squash with brown sugar and butter., learn how to cook acorn squash in two ways: sweet and savory. both are super easy and make for an fantastic side dish! one of the greatest things about fall is squash.