• Preheat the oven to 350°F. Line two 9" pans with parchment paper. Don't skip the parchment liner or it will be almost impossible to handle the cheesecake layers later.
• Combine the graham cracker crumbs, sugar and cinnamon in a mixing bowl. Pour the melted butter over the crumbs and toss to combine. Dump the crumbs into ONE of the prepared pans and pat down to an even layer.
• Bake the crust about 10 minutes until fragrant and just beginning to brown. Remove from the oven and set aside to cool. Leave the oven on.

Make the Cheesecake batter

• In a large mixer bowl or stand mixer bowl, use the beater attachment to cream the cream cheese until soft and smooth. You're not trying to add air, just soften the cream cheese. Keep the mixer on low speed. Scrape the bowl and the beater.
• Add the granulated sugar and lime zest, mix until no lumps of cream cheese remain. Scrape the bowl and paddle attachment again. Add the sour cream, scrape the bowl and paddle attachment again.
• With the mixer running on low speed add the eggs/yolk in 2 batches, Scrape the bowl and paddle attachment between batches. Add the vanilla and lime juice (2 tablespoons) and mix until combined.
• Divide the batter evenly between the two prepared pans. Set the pans into slightly larger pans and pour an inch of warm water into the larger pan.
• Bake until the center of the cheesecake is set (see note), about 15 minutes for the layer with no crust and about 20-25 minutes for the layer with the crust.
• Allow the layers to cool to room temperature then place the pans in the freezer several hours or overnight. The layers should be frozen solid.
• To remove the cheesecakes from the pans dip the bottom of the pan in a bowl of very hot water, run a knife or spatula around the sides of the cake and flip it out onto a flat plate. Alternately, you can flip the pan over and run a propane torch across the bottom of the pan. Remove the parchment round from the bottom and flip right side up. If not assembling the cake immediately, wrap the cheesecake layers and freeze until ready to use.

Assemble the Cake

• Warm the curd in the microwave and set it aside until it is room temperature but still soft and pourable.
• Place the frozen cheesecake layer with the graham cracker crust onto a serving platter, crust side down. Fill a piping bag with cream cheese frosting. Pipe a 1 inch "dam" of cream cheese frosting around the edge of the cheesecake layer.
• Pour 1 1/4 cups of lime curd onto the cake and spread evenly. The cream cheese "dam" will hold the curd in place until it sets.
• Set the other frozen cheesecake layer onto the curd filling. Ice the sides of the cake with cream cheese frosting. Press graham cracker crumbs onto the sides.
• Pipe a border around the top edge of the cake. Pour the remaining lime curd onto the cake and spread to a smooth finish.
• Refrigerate until the curd is set. Serve chilled.