Preheat your oven to 325°F (163°C). Prepare the springform pan by greasing it lightly.

In a large mixing bowl, combine graham cracker crumbs, granulated sugar, and melted unsalted butter. Press into the bottom of the pan. Bake for 10 minutes and let cool.

Beat softened cream cheese until smooth. Gradually add sugar and sour cream until combined.

Add eggs one at a time, then mix in vanilla extract, lemon zest, and fresh lemon juice until fragrant.

Fold in chilled heavy cream, cornstarch, and salt until well mixed.

Pour the cheesecake filling over the cooled crust and bake for 55-60 minutes, until the edges are set.

Turn off oven, cool cheesecake inside for 1 hour, then let cool completely before refrigerating for at least 4 hours.

Beat egg whites until foamy, add cream of tartar, and beat until soft peaks form. Gradually incorporate sugar for stiff peaks.

Drizzle lemon juice into meringue while beating to add flavor.

Spread meringue over cooled cheesecake, creating peaks. Bake again at 350°F (177°C) for 8-10 minutes until golden brown.

Let cool slightly, chill for 1 hour, then slice and serve.