Preheat oven to 375°F. Line a baking sheet with parchment paper. In a large mixing bowl, beat butter with an electric mixer on medium to high speed for 30 seconds. Add sugar, cocoa powder, and baking powder. Beat until combined, scraping sides of bowl occasionally. Beat in eggs until combined. Beat in as much of the flour as you can with the mixer. Stir in any remaining flour. Stir in the cranberries and almonds.
Shape dough into two 9-inch-long rolls. Place rolls on prepared cookie sheet; flatten slightly until about 2 inches wide.
Bake in the preheated oven for 20 to 25 minutes or until a wooden toothpick inserted near center comes out clean. Cool on cookie sheet for 1 hour. (For easier slicing, wrap cooled rolls in plastic wrap and let stand overnight at room temperature.)
Preheat oven to 325°F. Use a serrated knife to cut each roll diagonally into 1/2-inch slices. Place slices, cut sides down, on an ungreased cookie sheet. Bake in the preheated oven for 8 minutes. Turn slices over and bake for 9 to 11 minutes more or until dry and crisp. Transfer to a wire rack and let cool.
Microwave white chocolate and shortening in a small microwave-safe bowl on 70% power (medium) for 1 minute or until melted, stirring twice. Dip one long end of each cookie into the melted chocolate; let excess drip back into bowl. (Or drizzle chocolate over biscotti.) Place cookies on waxed paper; let stand until set.