Preheat oven to 225 degrees F. Line a baking sheet with parchment paper.
In a stand mixer bowl and using the whisk attachment, beat the egg whites and salt until it becomes foamy.
Add cream of tartar and beat until soft peak form.
While the mixer is in low speed, add the superfine sugar 1 tablespoon at a time until it’s all mixed in. Keep mixing until the egg whites becomes a stiff peak form.
Add the vanilla extract and mix evenly.
Pour in a pastry bag with a flower piping tip and pipe it to make a nest.
Bake for about 1 hour. Shut off the oven. Leave the meringues in the oven to dry out. After it’s cooled, store in an airtight container.
Lemon Curd
In a saucepan, whisk together lemon zest, lemon juice, white sugar, eggs and salt until combined.
Place saucepan on burner and put the stove to medium heat.
Stay with the saucepan and whisk continually for 15 minutes. This is to prevent egg from curdling. Curd will begin to thicken between 10 and 15 minutes.
After 15 minutes, remove from heat. Add the butter, 2 tablespoons at a time, and keep whisking until all the butter are completely mixed in.
Pour curd through a fine mesh strainer. This will remove the zest and any partially cooked egg.
Chill the curd for 3 hours or overnight before using. You want the curd to be nice and thick.
Once the meringue is dry overnight and the curd is set, pipe a little lemon curd in the middle of the meringue nest.