Put the eggs and the egg yolks in a tall, narrow bowl, drizzle in the oil and mix everything with a hand blender.

Place the mixture in a food mixer and add the flour and sugar first, then the lemon zest and vanilla extract. Knead the ingredients until you obtain a smooth pastry and let the dough rest in the fridge for about an hour.

Prepare the coffee and break up the chocolate. Then take a bowl and whisk the eggs, the egg yolks and the sugar, then add the cornflour.

In a large saucepan, put the water on the hob and bring to a boil, then pour the mixture of the eggs into the water and cook for about 2 minutes in order to obtain a dense dough. 

Add the previously prepared coffee, turn off the hob and add the broken chocolate. Mix with a whisk or a hand blender until the chocolate melts completely and at that point, let it cool.

Put 60 g (2 oz) of egg whites and 120 g (4 oz) of sugar in a bowl and whisk until the mixture becomes dense and fluffy. You'll know it is ready when the mixture stays well attached to the bottom of the bowl when you turn it upside down.

Once the cream has cooled, add about 50 g (1.8 oz) of meringue to every 150 g (5.3 oz) of cream and stir until you get a homogeneous mixture.

Sprinkle the pastry with icing sugar, fill it with the cream and decorate with the berries.