Preheat the oven to 350 degrees F and line a baking sheet with parchment paper. Whisk the flour, baking powder, cinnamon and salt in a medium bowl. Beat the butter and sugar in a large bowl with a mixer on medium-high speed until light and fluffy, 3 to 5 minutes. Beat in the eggs, liqueur, and almond and vanilla extracts until combined. Reduce the mixer speed to low; add the flour mixture and beat until just incorporated. Fold in the raw and chocolate-covered almonds.
Dust your hands and the dough with flour; divide in half and shape into two 3-by-12-inch logs on the prepared baking sheet, about 3 inches apart. Bake until puffed and set, about 25 minutes. Let cool 10 minutes on the baking sheet, then transfer to a cutting board.
Reduce the oven temperature to 250 degrees F. Slice the logs crosswise into 1-inch-thick pieces; arrange cut-side down on the baking sheet. Return to the oven and bake, flipping halfway through, until dry and golden, about 45 minutes. Let cool completely on the baking sheet.
Place the white chocolate and semisweet chocolate in 2 small microwave-safe bowls; microwave in 30-second intervals, stirring after each, until melted. Drizzle on the biscotti; let set 30 minutes.
Photograph by Andrew Purcell
Recipe courtesy of Food Network Magazine