Preheat your oven to 350°F (175°C). In a bowl, combine graham cracker crumbs, melted butter, and sugar. Mix until moistened, then press the mixture into the bottom of a 9-inch springform pan. Bake for 10 minutes and let it cool.

In a large mixing bowl, beat the softened cream cheese until smooth. Gradually add in sugar, mixing until combined. Add in the eggs, lemon juice, and lemon zest, blending until just combined.

Pour the cheesecake filling over the cooled crust and bake at 350°F (175°C) for about 50-60 minutes, or until the center is set but slightly jiggly. Turn off the oven, crack the oven door, and let the cheesecake cool in the oven for about an hour to prevent cracks.

In a saucepan, combine lemon juice, sugar, eggs, and lemon zest for the lemon curd. Cook over medium heat, stirring constantly until thickened (about 8-10 minutes). Stir in the butter until melted. Spread the lemon curd over the cooled cheesecake.

In a clean bowl, beat the egg whites and cream of tartar together until soft peaks form. Gradually add in the sugar, continuing to beat until glossy stiff peaks form.

Spread the meringue over the lemon curd layer, sealing the edges to prevent shrinking. Create swirls or peaks for extra flair.

Bake the meringue in a preheated oven at 350°F (175°C) for about 10-12 minutes until golden brown.

Carefully remove the cheesecake from the oven and let it cool before refrigerating for at least 4 hours (or overnight).