Puree the chopped apricots in a food processor or blender until very smooth. Measure out 200g of the puree (discarding any excess or saving for another use).

In a medium, heatproof bowl set over a saucepan of simmering water (creating a double boiler—ensure the water does not touch the bottom of the bowl), whisk together the apricot puree, sugar, egg yolks, whole egg, and lemon juice.

Continuously whisk the mixture constantly until it thickens significantly and coats the back of a spoon, reaching approximately 82°C (180°F) on a thermometer. This process usually takes 10-12 minutes.

Remove the bowl from the heat. Whisk in the cold butter cubes, one at a time, ensuring each piece is fully incorporated and emulsified before adding the next. Stir in the pinch of salt.

Strain the curd through a fine-mesh sieve into a clean bowl to ensure an ultra-smooth texture, pressing down on any solids with a spatula.

Press a sheet of plastic wrap directly onto the surface of the curd to prevent a skin from forming. Refrigerate for at least 4 hours, or until completely chilled and set.