In a large saucepan, add the egg yolks, the lemon juice, the sugar, the cornstarch and mix everything very well until combined.
Add the milk at room temperature, turn on the heat, set it to medium-low and stir the mixture continuously until it thickens.
Then, turn off the heat, add the white chocolate, mix everything very well until completely melted and set aside until the cream reaches room temperature.
Line a removable-bottom cake pan with parchment paper.
Add the chocolate-filled wafer rolls in a vertical position, filling the whole pan.
Then, add the cream we prepared on top of everything and arrange it evenly.
Take the dessert to the fridge and let it chill for at least 3 hours.
After this time has passed, unmold the dessert, decorate it with shredded coconut to taste and a slice of lemon.
Serve.