A simple yet fascinating dessert that forms three layers on its own—fluffy top, creamy custard middle, and a soft base—all from one batter.
Mix the zest of 2 lemons into the sugar and set aside.
Crack 10 eggs, placing whites in one bowl and yolks in a larger mixing bowl.
Add the flavored sugar to the yolks.
Whisk until the mixture lightens in color and triples in volume (you can use a mixer for ease).
Gradually incorporate 180 ml of melted, cooled butter and 2 teaspoons vanilla extract.
Gradually mix in ½ of the milk (from the total 1 liter).
Then add 200 g of flour and mix until smooth.
Finally, add the remaining milk and stir to combine.
Beat the egg whites with a pinch of salt until stiff peaks form.
Gently fold the egg whites into the batter in two additions, being careful not to deflate them too much.
Pour the batter into a tray (greased or lined with parchment).
Bake in a preheated oven at 150°C (300°F) for about 60 minutes, or until the top is golden and slightly firm.