Mix crumbs, sugar, and butter and press into bottom of a 9-inch
springform pan. Bake 10 minutes.
Beat cream cheese, sugar, flour, juice, peel, and vanilla at medium until well blended. Add the 3 whole
eggs and the egg white, 1 at a time, mixing well after each addition. Pour over crust.
Bake 40 minutes. Turn off oven and let cake cool as the oven cools down. Loosen cake from rim of pan.
Cool completely before removing rim.
Mix sugar and cornstarch in saucepan. Gradually stir in water and juice. Bring to a boil over medium heat,
stirring constantly. Boil 1 minute until clear and thickened, stirring constantly. Add small amount of hot
mixture to slightly beaten egg yolk. Return mixture to saucepan and cook 3 minutes, stirring constantly.
Cool slightly.
Spoon topping over cheesecake and refrigerate at least 2 hours.
Garnish with paper-thin slices of lime
* I use regular lime peel and slices since I have no source for fresh
key limes. If you do, all the better. I get the key lime juice from the King Arthur catalog.