Preaheat oven to 375 and place rack in the center. Line a baking sheet with parchment paper or silpat. in a large bowl, whisk flour, sugar, cocoa, baking powder and sale untl combinted. Add buttter. Use your fingertips to rub it into the flour until the butter is pea size and misture is coarse. IN a separate bowl, whisk together the egg and crea. slowly pour the wet ingredients into the dry ingredients and stir untilj the dough just comes together. Gently and briefly knead dough with your hands. [use just your fingertips like a fork]. Add the nuts and knead gently to incorporate. Flatten dough into a rectangle approximetly 6 by 12 inxhes. it does not need to be precise. spread 1/4 cup of Nutella on top. Roll the dough up to make a cylinder about 6 inches long, turn it on its end, and gently flatten it inot a disk about 13/4 inches high. Do Not Overwork the dough.