Start by making the mango puree. Add the mango to a blender or food processor and blend it into a smooth puree.
Set up a double boiler with a large pot or a saucepan. Combine the sweet mango puree with the egg yolks, salt and sugar in a bowl, place the bowl over the saucepan and cook it over medium heat whisking it continuously using a rubber spatula until the mixture thickens.
While the mixture is still hot, add the butter and whisk it all once again until well combined.
Now add the fresh lemon juice, give it a quick stir and your fresh mango curd is ready to be used.
Refrigerate the warm curd for at least 3-4 hours, if not more before using the mango curd.