Prepare the mixture by whipping the egg yolks with 75 g of sugar until the mixture is light and frothy (use a whisk or a planetary mixer with a whisk attachment).
Add the pinch of salt, the milk and the oil and continue to whisk.
Add the sifted flour.
Separately, beat the egg whites and as soon as they start to foam, add the remaining 75 g of sugar and continue to beat until you obtain a very firm mixture, like meringue. Add the egg white mixture to the egg yolk mixture delicately, with a spatula and movements from the bottom upwards.
Pour 1/3 of the mixture into a bowl and add some red food coloring. Mix well and pour into a small plumcake mold (if you have one) or a low pan, lined with baking paper.
Line a 23 x 30 cm baking tray with baking paper.
Pour the mixture and level with a spatula. Tap the pan on the counter to release any bubbles.
Bake at 180° for 15/20 minutes. Remove from the oven and leave to cool on a rack.
Meanwhile, prepare the pistachio cream.
Soak the gelatine in cold water. Heat 2 tablespoons of cream. Squeeze the gelatine and dissolve it in the hot cream, stirring.
Whip the mascarpone with the cream and the pistachio cream. Add the cream with the gelatin and whip again.
Spread the cream on the biscuit dough. Cut out little hearts from the red dough using a heart-shaped cutter/cookie cutter. Place the hearts on the cream. Roll up to form a roll without a spiral, joining the ends. I rolled everything up with cling film before putting it in the fridge to rest for at least two hours (even overnight is fine).
Before serving I cut the ends to have a more defined roll. I printed a sheet decorated with little hearts (you can find them online for free to print). I cut out the little hearts and used it as a stencil by placing it on the roll and sprinkling the icing sugar.