Place baking sheet on middle rack in oven. Heat oven to 400ºF.
Combine sugar, flour & salt in bowl.
Whisk in heavy cream, cinnamon & vanilla.
Pour into pie shell.
Place on preheated cookie sheet.
Bake at 400ºF for 10 minutes.
Reduce temp. to 375ºF.
Bake 10-15 minutes longer, until golden and just bubbly around edges.
If edges brown too quickly, cover loosely with foil.
Cool on rack (if you can wait that long).