Heat the butter with sugar, lemon juice and grated lemon zest in a water bath and stir with the whisk until the sugar has dissolved. Take the saucepan off the hob and stir the eggs into the lemon cream. Heat again carefully for about 5 minutes, stirring constantly, until the mixture has finally become creamy and thick. Stir the cream in an ice-water bath and pour it into 2 boiled screw-top jars. The lemon curd will keep in the refrigerator for about 2-3 weeks.
Knead all the dough ingredients quickly to form a dough, wrap in cling film and refrigerate for at least 1/2 hour. Then roll out the dough on a lightly floured surface approx. 0.5 cm thick and e.g., cut out circles approx. 7-8 cm in diameter with a wine glass. Place these in the hollow of a greased muffin tin and then bake in the oven preheated to 180 ° C for about 10-15 minutes.
Fill the cooled tartelettes with the lemon curd as required.