In large mixing bowl, combine flour, baking powder, salt, and sugar. Combine well. Add eggs and toasted almonds, and mix well until all ingredients are combined fully.

Cut room temperature butter into cubes, and add to dough mixture, being sure all ingredients are blended well, but careful not to mix too long as butter will lose its consistency and dough will become overly sticky.

Preheat oven to 175C.  Lightly beat egg for wash, set aside.

Divide prepared dough into three equal parts, and roll out each using your hands. Shape into cylinder or tube shapes approximately 3cm wide. Place wax paper onto baking tray, and place each dough cylinder on top of lined tray. Brush with beaten egg for wash and sprinkle with additional granulated sugar - during baking process the sugar will caramelize and add extra crunch to the cantuccini.

Bake in preheated oven for about 20 minutes.

Remove baked cookie cylinders from oven and allow to cool 1-2 minutes so they solidify their shape. While still hot, slice each cylinder diagonally into pieces 1cm thick. These will become your cantuccini.  Lower oven temperature to 140C.

Place cookies back into hot oven on baking tray and allow to cook another 5 minutes. Remove from heat, allow to cool completely.

Serve cooled cookies at room temperature accompanied by Tuscan Vin Santo.