How to make
Sift the flour on the counter, make a well in the middle and put in the sugar and salt, beaten egg with 2 tbsp (30 ml) of lukewarm water. Cut the cold butter into small cubes and distribute it around the well in the flour.
Chop everything with a knife until crumbs form. Then shape it into a ball with your hands, cover with transparent foil and leave it in the refrigerator for about 30 minutes.
Grease a cake form with a diameter of about 10 1/4″ (26 cm) and sprinkle it with flour. Roll out the dough between 2 sheets of baking paper and place it in the form. Form an edge and cut off the rough parts, prick the layer with a fork. Heat the oven to 360°F (180 °C). Melt the couverture chocolate and butter in a water bath.
Separate the eggs into yolks and whites. Beat the yolks with the sugar, lemon zest and vanilla. Add the chocolate mixture to these. Add the egg whites that you've beaten into hard snow with the lemon juice. Sprinkle starch and stir everything gently.
Pour the filling over the layer and smooth it out. Bake on the lower element of the oven for about 45 minutes. Remove from the oven, leave it to rest for some time in the form, then cool it.
Source: chocolate for modern people.
