Position rack in center of oven; preheat to 350 degrees F. Line 2 large baking sheets with parchment paper or nonstick baking mats.

Toss dried cherries and raisins with rum in a small bowl. Set aside.

Pulse oats in a food processor until ground to a coarse, but uniform, meal.

Whisk the ground oats, flour, baking powder, baking soda, salt and cardamom in a medium bowl. Beat eggs, sugar and butter in a mixing bowl with an electric mixer on high speed until light and fluffy, about 2 minutes. Beat in orange zest, vanilla and almond extracts. With the mixer on low, gradually add the dry ingredients just until incorporated. Add the reserved dried fruit, along with any unabsorbed rum, pecans and chocolate and mix on low until evenly distributed.

On one of the prepared baking sheets, shape the dough into two 12-by-2 1/2-inch logs. (The dough is sticky: wet or oiled hands make it easier to shape into a log.) Bake in the center of the oven until lightly browned and feels set when gently touched, about 25 minutes. Let cool on the baking sheet for 10 minutes.

Reduce the oven temperature to 300 degrees ; reposition the racks to the upper and lower thirds of the oven. Using a serrated knife with a gentle sawing motion, slice the partially cooled logs on a slight angle into 1/2-inch-thick slices. Place the slices, cut-side down, on the 2 baking sheets.

Bake the biscotti until they're dry on top and lightly toasted on the bottom, about 15 minutes. Turn over and bake for 15 minutes more on the second side. Transfer to a wire rack to cool.