In a stainless mixing bowl, add in the eggs, sugar, lemon juice, lemon zest, and salt. Whisk until combined.

Over simmering water (double boiler, aka bain marie), cook slowly until lightly thickened. Stir constantly. As the eggs cook, the mixture will thicken and turn light yellow.

Remove from heat when it coats the back of a spoon. Add in diced butter and stir until combined. As it cools, it will thicken more.

To make meringues:

Preheat oven to 100 degrees F (95 degrees C).

Place egg whites in a stand mixer (make sure it’s clean) fitted with the whisk attachment. Whisk on low allowing bubbles to form, increase to high and continue whisking until stiff peaks form and you can turn the bowl upside down without the egg whites falling out.

Add one big spoonful of sugar at a time, ensuring that the whites come back to stiff peaks after each addition. Once all the sugar is added, continue to whisk for 5 – 7 minutes. You should be able to rub the mixture between your fingers and not feel any grit from the sugar. You know it’s ready to use when it forms a smooth shiny peak on the tip of your finger. Add a pinch of salt.

Line baking sheet with parchment paper. Place a dab of meringue on four corners of pan and press paper on top to hold it down flat. Pipe meringues on baking sheet, and bake for 2-3 hours until meringues can easily be lifted off parchment paper with bases intact. The inside should be dry as well. Let cool completely in the oven, preferably overnight. Store in airtight container. Pipe lemon curd to the centre on the day you serve them.