Countertop: Separate the eggs, mix the egg whites with a pinch of salt until they start to foam. Gradually add the sugar, mix until the meringue is hard. Mix the yolks with the oil and milk, add them over the egg whites and mix well. Sift flour, cocoa and baking powder, gradually incorporate them with a silicone palette. Finally add the vanilla. Wallpaper a large stove tray with baking paper, pour the top composition. Level it, then put it in the hot oven, at 180 degrees, for 12-14 minutes. When ready, remove the top from the oven, peel it off the baking paper. Roll it hot to take shape and let it cool.
Vanilla cream: In a saucepan, mix the milk with the sugar and starch, until the latter is completely dissolved. Transfer the pan to the heat, let the heat be low, stir continuously with a whisk, until the cream thickens like a pudding. Set it aside when it's ready, cover it with foil and let it cool. When the cream has cooled, mix it a little, then add the mascarpone, vanilla and mix until they are all incorporated. Wash some strawberries, remove the stalks and cut them into pieces. Open the cold countertop, put the cream and level it. Place the strawberry and mint jelly pieces in place. Start and roll gently, put the roll in foil and tighten it well at the ends. Let it cool for 3-4 hours. Melt the dark chocolate on a steam bath with liquid cream. Slice the roll, put melted chocolate on it, sprinkle some chocolate chips and you can serve.
PS: The cream seemed a bit much to me, because when I ran it, it came out of it. Because of this I could not put more fruit. So if you want to put more fruit, make less cream.