How to make
Separate the egg whites from the yolks. Beat the yolks with a mixer on very high with the lemon zest and a pinch of salt. Put the container in a water bath on the stove and stir until it changes color slightly.
Be careful not to cook the yolks. Stir constantly and gradually add the milk and sugar. Set aside 2 tablespoons of it.
Add some water, dissolve a little starch and stir vigorously. Distribute the homogenized cream into custard bowls. Put it in the refrigerator for several hours. When serving, sprinkle each with sugar and heat it to caramelize. Add the starch and mix again so there's no lumps.
When it's ready pour into individual cups and put in the fridge.
When serving the Catalan custard, sprinkle with sugar and heat until caramelized.
