Preheat your oven to 350°F (175°C). Grease a 9-inch springform pan and line the bottom with parchment paper.

Mix graham cracker crumbs, sugar, and melted butter. Press into the pan and bake for 10 minutes. Let cool.

Beat cream cheese until smooth. Add sugar, then eggs one at a time. Mix in lemon juice, zest, and sour cream until smooth.

Pour the filling into the crust and bake for 45-50 minutes until edges are set but center is slightly jiggly. Let cool, then refrigerate.

Whisk eggs and sugar in a saucepan. Add lemon juice, butter, and zest. Cook over medium heat, stirring until thickened. Let cool.

Spread the cooled lemon curd evenly over the chilled cheesecake.

Beat egg whites and cream of tartar until soft peaks form. Gradually add sugar and beat to stiff peaks.

Spread meringue over the lemon curd, creating peaks with a spatula.

Bake for 10-15 minutes until golden brown. Watch closely to prevent burning.

Let cool to room temperature, then chill for at least 2 hours before serving.