Preheat stove to 180 degrees.
Mix baking soda, flour, salt and cocoa, sift. Beat butter with sugar until creamy, fold in eggs. Fold in pistachios and chocolate, chopped.
Form 25 cm long rolls from the dough. Place on a baking sheet covered with parchment paper and press a little flat. Bake for 25 minutes, remove from heat, cool for 5 to 10 minutes.
Turn down the heat to 150 degrees.
Cut rolls diagonally into 2 cm slices with a serrated knife. Place cut side down on baking sheet and bake for another 10 minutes.