Position your oven rack in the center position and preheat your oven to 350 degrees. Place a jelly roll pan on the baking rack to preheat with the oven. You will be setting your cheesecake on this pan later (explanation will come shortly).
Butter a 9.5 to 10-inch springform cake pan with 1 tablespoon of softened butter. Note: This is a very crucial step in the baking process! Remember that baked goods stick to pans more persistently at higher altitudes; be sure to butter your entire pan, or neither the crust nor the cake itself will yield when you release the pan's springform. You don't want to ruin the aesthetic of your cheesecake in the process of violently yanking it out the pan! The more butter, the less likely the cake will stick. I myself had trouble getting the cake out of the pan -- the tablespoon didn't seem enough. Don't be afraid to use more. Seriously.
Make the crust by tossing the graham cracker crumbs, almonds, and granulated sugar with the melted butter. Note: Pie in the Sky called for a cup of finely chopped almonds; while I used a Cuisinart food processor to chop up the majority of a 2 oz bag of almonds, I left a handful of whole almonds to be patted down in the crust. I received several compliments on this during dinner -- it adds a unique touch to normally indistinguishable crust.
Press the crumbs evenly onto the pan bottom and set aside. This is what the pan should look like once you have finished patting down the crust:
Beat the cream cheese in a large mixer bowl until very smooth and soft (if you are using a KitchenAid mixer, use the flat paddle attachment). Add the sugar and beat until creamy. Scrape down the bowl and beater.
Beat in the sour cream, cornstarch, and salt. One at a time, beat in the eggs. Scrape in the bowl and beaters again.
Beat in the lemonade concentrate, fruit extracts, and zest. Scrape the bowl one last time to make sure the batter is smooth, and continue to beat for about a minute after. Be careful not beat too much after you've added in the eggs -- doing so will add too much air to the batter, causing unattractive bubbles to rise to the surface.
Scoop the batter into the buttered and crusted springform pan. Set the pan on the jelly roll pan and bake for 50 to 55 minutes. When the cake is ready, the edges will have puffed up and the top of the cake will be a golden color with a few cracks near the rim. The cake center will still look soft, but not jiggly or fluid when the side of the pan is tapped.
Remove the cake and set it on a wire rack in a draft-free location to cool. To prevent cracking, cover the top with a cardboard cake disk. Cool completely for several hours, then refrigerate overnight to allow the texture to firm up.