Double Stuffed Vanilla Key Lime Pie

1. Preheat the oven to 350 degrees F.
2. In a bowl, mix the graham cracker crumbs, cinnamon, and butter until combined. Press the mix into a deep-dish 9-inch pie plate. Transfer to the oven and bake until toasted, about 8 minutes.
3. Meanwhile, whisk the egg yolks in a medium bowl until smooth. Add the sweetened condensed milk, lime zest, lime juice, vanilla, vanilla bean powder (if using), and salt. Whisk to thoroughly combine. Carefully pour the mix into the baked crust. 
4. Transfer to the oven and bake for 13-14 minutes, until just set on top. Let the pie cool slightly, then cover and chill in the fridge until set, at least one hour. Serve the pie topped with whipped cream and additional lime zest.