I found this recipe many many years ago. When my son was younger, he would not touch squash. The first time I made this I didn't tell him it had squash in it and he ate it like crazy. When he learned that it had squash in it he could not believe it. My family is grown now but still request this dish even my son but this is the only way he will it squash.
Saute onion and celery in 1/4 margarine until softened, but not browned. Put remaining butter in cooked squash ; mash and mix well. In large mixing bowl, combine milk and soup, and add to squash mixture and mix well.add onion and celery ;mix well. Crumble cornbread into squash mixture and mix well. Sprinkle poultry seasoning, sage, and salt and pepper over squash mixture, stirring until all ingredients are well combined. Pour mixture into greased 13 by 9- inch baking dish and bake uncovered at 350 degrees for 30 minutes.