Preheat oven to 350 degrees F. Butter a 9-inch cake pan. Set aside.
Using a 3-inch round cutter, punch out 11 circles from the sliced bread. Take the remaining bread scraps and tear them into small pieces. Take about 1/3 of the scraps and spread half with peanut butter and the other half with Nutella. Place all the scraps into the prepared cake pan. Push down to compact the bread scraps.
In a large bowl, whisk together cream, milk, vanilla, yolks, eggs, sugar, and salt. Whisk until sugar dissolves. Pour half of the custard over bread scraps.
Spread peanut butter on half of the bread rounds. Spread Nutella on the remaining rounds. Arrange the bread rounds spread side down on top of the bread scraps. Arrange the rounds in an overlapping patter to create a shingle. Place the last bread round in the center. Pour the remaining custard over the bread.
Place the cake pan into a roasting pan. Fill the roasting pan with hot water until the cake pan is halfway submerged. Cover the roasting pan with a foil tent, allowing the cake room to expand. Bake for 35 minutes. Remove foil and continue baking for another 30 minutes. By this time the custard should be set and the bread golden brown. Remove from oven and remove cake pan from water bath. Let bread pudding sit for 5-10 minutes to cool. Dust with sifted powdered sugar and garnish with chopped toasted hazelnuts and chocolate chips before serving. Serve warm.