Make the recipe for lemon curd. This is best done the day before, or at least four hours ahead of time so it has time to chill.
Preheat the oven to 325 degrees F. Cover the outside an 8" springform pan with aluminum foil.
Add the graham cracker crumbs to a food processor. Run the food processor and drizzle in the melted butter. It should come together like wet sand.
Add the graham cracker crumbs to the springform pan. Use the bottom and sides of a glass to press the crumbs to the bottom and sides of the pan. Make sure it is well packed together. Set aside in the refrigerator until needed.
Add the cream cheese to a mixing bowl and beat with a paddle attachment until it is smooth and creamy. Scrape down the sides and bottom of the bowl as needed and as you add each ingredient.
Add the eggs in one at a time. Beat in each egg until adding another. Make sure each egg is completely combined with the cream cheese before you add in the next.
Pour in the sugar, lemon zest, and vanilla and mix until the mixture is smooth again.
Slowly add in the sour cream one cup at a time until it is thoroughly mixed in. Do not overmix.
Fold ½ cup of the lemon curd into the batter. You can either leave swirls of the curd in the batter or completely combine the curd into the batter.
Pour the batter into the springform pan and bake for 45 minutes. The edges should look mostly set and the center will look jiggly still. Turn off the heat and keep the oven door cracked open with the cheesecake inside for an hour. This helps prevent the cheesecake from cracking.
Remove the cheesecake and allow to cool completely to room temperature.
Once the cheesecake is fully cooled (I chilled mine in the refrigerator for 30 minutes once it was cooled), top with more lemon curd.
As the cheesecake is cooling, make the meringue. Clean a mixing bowl and whisk and thoroughly dry. Quickly rub down with lemon juice.
Add the egg whites to the bowl and beat. While you are beating the whites, add the sugar and water to a small saucepan and heat without stirring until the sugar dissolves.
Add cream of tartar and salt to the egg whites. Once the egg whites form soft peaks, turn up the speed of your mixer and drizzle in the sugar syrup between the bowl and the whisk. Continue to beat until the whites form stiff, glossy peaks. Beat in the vanilla.
Fit a piping bag with a large tip and fill with the meringue (or use a spoon) and top the cheesecake with the meringue. Lightly torch using a kitchen torch.
Serve immediately. If you are not serving immediately, save the meringue until you are ready to serve.