For the walnut cantuccini, beat eggs, yolks, sugar and salt until foamy. Fold in flour, baking powder and walnuts. Form 4 rolls from the dough and place them on a baking tray lined with baking paper.
Bake in the preheated oven at 175 degrees top/bottom heat for about 35 minutes until golden brown. Remove from the oven and cut the rolls while still hot into slices about 1 cm thick.
Place the cut side on the baking tray and let the walnut cantuccini dry in the switched off, still warm oven.