Preheat the oven to 325°F (160°C). Prepare the springform pan by greasing it lightly.
In a mixing bowl, combine graham cracker crumbs, granulated sugar, and melted butter. Press the mixture into the bottom of the springform pan.
In another bowl, beat the cream cheese until smooth. Gradually add granulated sugar, lemon juice, lemon zest, sour cream, and eggs, mixing until well combined.
Pour the cheesecake filling over the crust and bake for 50-60 minutes or until set. Let cool.
To make the lemon curd, melt the butter in a saucepan. Whisk in sugar, eggs, lemon juice, and lemon zest. Cook over low heat until thickened.
Spread the lemon curd over the cooled cheesecake.
For the meringue, beat egg whites and cream of tartar until soft peaks form. Gradually add sugar and continue beating until stiff peaks form.
Spread meringue over the lemon curd and bake for an additional 10 minutes until lightly browned.
Allow the cheesecake to cool before serving.
Notes
Chill the cheesecake for several hours or overnight for the best flavor and texture.