Step 1

Soak the gelatin in cold water. Heat the milk with the vanilla bean pod opened lengthwise. Melt the butter together with the condensed milk. Incorporate the cornstarch. Pour the filtered milk over the butter and combine, then add in the drained gelatin and let it melt. Divide the cream between two containers; add the chopped white chocolate to one and the chopped gianduja chocolate to the other. Spoon them into a silicone mold (1 quart capacity) moistened with a bit of rum, alternating the two mixtures.

Step 2

Let the custard chill, then refrigerate for 4 hours. Chill in the freezer for 30 minutes, so you can remove it from the mold more easily; leave at room temperature for 30 minutes before serving, garnished with toasted hazelnuts.