Begin by peeling, pitting, and chopping the peaches. Place the chopped fruit into a blender and purée until smooth, aiming for approximately 1 cup of peach purée.

Fill the double boiler with water and bring it to a rolling boil over medium heat. Reduce to simmer.

In the top part of the double boiler, combine egg yolks, sugar, lemon juice, salt, and peach purée. Whisk until smooth.

Place the top bowl over simmering water, whisking continuously for about 15 minutes until mixture thickens and coats the back of a spoon.

Remove from heat and slowly whisk in the unsalted butter until fully melted and incorporated.

Cover the surface of the curd with plastic wrap to prevent a skin from forming. Allow to cool at room temperature for 30 minutes, then refrigerate for 2 hours.

Store the cooled peach curd in an airtight container in the refrigerator for up to a month.