Whisk all ingredients together in a large bowl, then scrape into an unbaked 9" pie shell. Bake 15 minutes, then reduce to 325ºF and bake 40 minutes more, or until pie is set (it'll still be a bit jiggly, but not loose). Cool on wire rack and serve warm, room temperature, or chilled, topped with whipped cream. Store cooled pie (and any leftovers) in the refrigerator.