Zest two to three lemons until you have 3 tablespoons of zest.

Cut and juice the lemons until there is ½ cup of lemon juice - remove any seeds.

Cut the butter into tablespoon pieces and place a fine mesh sieve on top of a bowl.

Rub together the sugar and lemon zest until it turns pale yellow and very fragrant. Whisk in the cornstarch until evenly distributed.

Transfer the sugar mixture to a medium saucepan and add the eggs and lemon juice and place over medium-low heat.

Whisk constantly until the curd thickens considerably and coat the back of a spoon. About 5 minutes.

Transfer the curd to the fine mesh sieve and pass it through into the bowl using a rubber spatula or wooden spoon. Scrape the underside of the sieve to remove all curd.

Add in the pieces of butter and whisk until completely melted, incorporated, and smooth.

Cover the lemon curd with plastic wrap, placing the wrap directly onto the curd to prevent a skin from forming.

Chill in the refrigerator for at least 2 hours before using or eating.

Whisk together flour, cornstarch, baking powder and salt and set aside.

Using fingertips, mix together sugar and lemon zest until pale yellow and very fragrant.

Cream together the butter, sugar, and oil until pale in color, about 5 minutes. Add the egg and vanilla and beat again for one minute. Scrape down the sides.

Whisk together the sour cream and whole milk.

With the mixer running on low speed, add half of the flour mixture, then half of the milk mixture. Scrape down the sides and repeat until the batter is completely moistened.

Divide the batter evenly between the two cake pans then bake in the center rack for 28-32 minutes or until a toothpick inserted into the center comes out clean with no wet batter.

Cool in the pan for 10 minutes, then remove the cake from the pan and finish cooling for another 30 minutes, or until no longer warm to the touch.

If storage is needed, wrap the cake layers tightly in plastic wrap and store at room temperature for 24 hours, or in the freezer if storage is needed for longer.

Fill a saucepan with about two inches of water and turn to high heat. Add a heat proof bowl over top that fits securely. You don’t want any of the water touching the bottom of the bowl.

To the bowl, add the egg whites, sugar, and salt and whisk to combine. Continue lightly whisking until the mixture is rather warm and the sugar granules have dissolved. Check this by rubbing your fingers together in the mixture. If you can still feel sugar granules, continue cooking.

If needed, use a serrated knife to cut off the domed tops of the cake rounds so it’s a nice, even cake layer.

Add one large dollop of meringue to a piping bag or ziptop bag and cut off a ½” tip.

Add one layer of cake to a cake stand and pipe a border around the edge of the cake. Use an offset spatula or butter knife to pull the insides down to touch the cake. This ensures none of the filling will escape.

Fill the inside of the border with lemon curd (not allowing it to go over the border), then very gently place the second cake layer evenly on top. Do not press down.

Add a large amount of meringue to the top of the cake and begin working it down the sides, fully covering the cake.

Add the remaining meringue, and use the back of a spoon to create swoops all over.

Use a hand torch to lightly toast the meringue, then slice and serve.