Make the Lemon Curd: Use a non-metal pan, if at all possible. It can react with the lemon and leave a metallic taste. Use a ceramic pan and even a silicone whisk if you've had issues with this in the past. I haven't, but have heard of it happening to others. Beat the eggs in a small bowl and set aside. Place a strainer over a medium bowl. Add lemon zest and sugar to a medium saucepan, rubbing the lemon zest into the sugar well with clean fingers. Add the lemon juice, beaten eggs, and salt to the same pot. Whisk until well combined. Cook, whisking constantly, over low heat, for 10-14 minutes or until the temperature on a candy thermometer reaches 175° F. The mixture should coat the back of a spoon, and hold a trail when you drag your finger through the curd. Remove the saucepan from the heat immediately once it hits 175℉, and strain it into the medium bowl to remove any lumps. Whisk the vanilla & butter into the hot curd mixture until fully combined. Press plastic wrap onto the surface of the curd and chill in the fridge at least 3 hours or up to 4 days week before using. Curd will thicken a bit as it cools.Tip: Use a bit of golden yellow food coloring to make this look more lemony – it is naturally less saturated than mine looks. Note: This yields about 2 cups, or 555 grams of lemon curd.

Make the Crust: Preheat oven to 350° F. Spray a 9-inch springform pan with nonstick spray and make sure the bottom is securely fastened. Stir together crust ingredients and press into prepared pan and up the sides a bit (see photos above). Bake this for 10 minutes. Set aside to cool, then wrap the bottom with foil. Tip: If your crust seems like it needs a bit more moisture, add 1-2 additional tbsp melted butter. I have to do this often lately!Keep the oven on at 350. Make sure your oven rack is positioned in the center. Fill a large pot with water and set it on your stove, and get out a large roasting pan – you'll need this for your water bath later.

Make the Cheesecake Filling: Remember that your cold ingredients need to come to room temp before you start or the filling may have issues. In a small bowl, rub the lemon zest into the granulated sugar with clean hands, until it resembles a sandy mixture. In a large mixing bowl, beat the softened cream cheese with electric mixer until creamy, about 1-2 minutes. Add the sugar & mix until well incorporated, about 1-2 minutes. Scrape the sides and bottom of the bowl with a rubber spatula as you go - little lumps of cream cheese love to hide down there. Add the eggs one at a time, mixing on medium speed after each until just incorporated - don't over mix here - we aren't trying to make a soufflé. Scrape down to the bottom of the bowl in between each egg. Add the vanilla, sour cream, and lemon juice and mix until just incorporated.Remove 2 and ½ cups (560 grams) of batter and add to a medium bowl. Fold in 1 cup of the chilled lemon curd. Add a little more golden yellow food coloring if desired. Alternate adding dollops of the two batters to the baked & cooled crust, using up all the batter. Use a butter knife to swirl the batters together for a pretty design.

Prepare the Water Bath + Bake: Bring the large pot of water to a boil. Set your springform pan with the cheesecake batter inside of a 10-inch cake pan, then place that stack into your roasting pan. Place the roasting pan in the oven, then pour the boiling water into the roasting pan only. Tips: The 10-inch cake pan is the only way to ensure your water bath doesn't leak into the cheesecake. Foil alone is not enough, I've learned from countless attempts. If you don't have a metal pan to use as a barrier between the springform cheesecake pan and the water, place the roasting pan of boiling water on the rack below your cheesecake pan. This method doesn't work as well than placing it in the water, but it's better than no water bath! The cheesecake will still taste delicious - this helps prevent cracks and helps it cook evenly.

Bake: Bake the cheesecake for 1 hour and 40 minutes to 2 hours and 12 minutes. When done, the cheesecake will have only a slight wobble in the center, and a knife inserted into the edge will come out clean, and will have just a bit of thick batter when inserted into the center.Turn off the oven and crack the door open. Let the cheesecake cool in the oven for 1 hour before removing it.

Cheesecake Cooling: Once the hour is up, remove the pan from the oven. It should be cool enough to handle. Remove the foil and set the springform pan on a wire rack. Let cool completely at room temp, then cover with foil and refrigerate at least overnight or up to 2 days before removing from the pan and decorating/serving.

Meringue Prep: Make sure you read the note below on cleaning your utensils with vinegar before beginning. Get out everything you need before starting, including your cheesecake. Place your cheesecake on a serving plate, and spread a thin layer of lemon curd on top. I have had better success making meringue in a stand mixer, but if you're confident with your hand mixer, you can use it as well. Try to avoid making this on a humid day as that can wreak havoc on the meringue's stability.

Make the Meringue: Add an inch or so of water to a small/medium saucepan. Make sure your bowl doesn't sit in the water. Test it by setting the bowl on the pot, over the water, lifting off and seeing if the bottom is wet. If you have a stand mixer, you can use it's metal bowl. In your selected bowl, whisk together room temperature egg whites, granulated sugar, cream of tartar, and salt. Set the bowl over the pot of water. Turn the heat to low, then cook, whisking constantly until an instant thermometer holds steady at 175℉. (Mine was registering between 175℉ and 180℉ depending on where I stuck the thermometer without hitting the bottom of the bowl. Keep going until you don't see any reading below 175 ℉.) This will take about 8 minutes, but go by temp, not by time. Remove from the heat immediately, and add the vanilla. Hand Mixer: Beat with a hand mixer on high speed for 4-5 minutes. We're looking for a thick mixture with stiff peaks. Stand Mixer: Mix with the whisk attachment on high speed (I like to keep it between 8-9, not at 10) for 4-5 minutes. The mixture will grow up the sides of the bowl, and is ready when it seems to have stopped growing, and is balling up inside the whisk attachment (it will almost look a tad clumpy, as opposed to smooth & silky). When you lift the whisk attachment out and flip it so the bottom is pointing up, the meringue should stand stiffly up, with only the slightest bit of the tip top strand of meringue flipping over. Immediately pile the meringue on your cheesecake, then gently make swirls with the back of a spoon. Toast the meringue with a blow torch.

Serve & Store: After toasting, immediately slice and enjoy! Store leftovers in an airtight container (a cake carrier works well here for the height of the meringue!) in the fridge for 3-4 days.