For the birthday train, cream the butter with the sugar. Add the eggs and beat until creamy. Mix the flour with the baking powder and sift over the mixture and stir in.
Chop 50 g of chocolate lentils and stir into the batter. If the dough is too firm, add a little milk. Pour the dough into a silicone baking pan and bake in a preheated oven at 180 °C for about 35 minutes (test with a stick).
Let the baked pastry cool down a bit in the pan, then turn it out onto a cooling rack to cool down completely. Drape the zucg on a platter and decorate with the remaining chocolate lentils.
Place a birthday candle in the center of the plate.