Why is my pumpkin pie filling expanding and cracking so much? I'm baking at 350 for about 45 minutes in a convection oven. Is it overcooked?

Yes, as Erin McDowell explains: "The proteins in eggs are wonderful but slightly fickle; if they are overbaked, they can contract, creating a pie with visible cracks on the surface." But that's nothing a little whipped cream can't hide! And next time you might want to try her Pumpkin Sugar Pie, it won't ever crack! https://food52.com/recipes/74133-pumpkin-sugar-pie