- Position a rack in center of oven. Preheat to 325 degrees (300 degrees if using a convection oven). Line a baking sheet with parchment paper or nonstick liner.
- Sift together flour, cocoa powder, baking powder, and salt.
- In a large stand mixer bowl, combine sugar and tangerine zest. Using the paddle attachment, rub the zest into the sugar to release the tangerine oil. Add in the flour mixture, almonds, chocolate, and cocoa nibs. Mix until well blended.
- In a small bowl, stir together eggs, egg yolk, honey, and vanilla until well blended. Pour egg mixture over dry ingredients, and mix well. Note: The mixture will feel dry at first, and then it will come together to form a wet dough.
- Scrape dough onto center of prepared baking sheet. Using damp hands, shape it into a log about 14 inches long and 3 inches wide. Rewet your hands if dough gets sticky.
- Bake for 36－38 minutes (30－34 minutes for convection ovens), until log gives slightly when pressed. Do not over-bake or it will be difficult to cut neatly.
- Move baking sheet to a wire rack and let cool completely, about 2 hours. Don’t be tempted to cut while warm—the chocolate will ooze and the slices will be very crumbly. Note: At this point, biscotti can also be covered and stored at room temperature for up to 1 day before proceeding.
- Reduce oven temperature to 275 degrees (250 degrees for convection ovens).
- Carefully remove log from parchment paper or liner and place on a cutting board. Using a serrated knife, cut log on the diagonal into ½-inch-thick slices.
- Line the baking sheet with a fresh sheet of parchment paper or nonstick liner.
- Place slices on baking sheet, cut side down, leaving a little space between them. Bake for 18－20 minutes (15－18 minutes for convection ovens), until they are dry. The second bake creates that great crunchy biscotti texture. To test for doneness, pull one out of the oven after 18 minutes and let it cool slightly. It should be very dry and firm—if it feels right, pull baking sheet out, set it on a wire rack, and let biscotti cool completely.
- Store in an airtight container for up to 2 weeks. The longer the biscotti sits, the more the flavor develops. In Miami, humidity tends to soften the biscotti, so before serving, I throw them in the oven at a low temperature, about 250 degrees, for 5 minutes, just until they are dry. If your weather is similar, I suggest you do the same.
Editor’s Note: Cocoa nibs pack a powerful chocolate flavor. They are dried, roasted, and crushed cacao beans. Crunchy and tender at the same, cocoa nibs have a special flavor. Use them in ice creams, cookies, cakes, and muffins.