By: Emily Luchetti, Special to the San Francisco Chronicle

Here in the United States, when we say biscotti we are referring to the twice-baked cookie that originated in the town of Prato outside Florence.

Because they contain no perishable ingredients like butter, and because they are baked dry, they have a long shelf life, making them ideal for taking on trips or storing in the pantry for a long time. Dipped in Vin Santo or an espresso, they are the perfect sweet little bite at the end of dinner.

In the Bay Area, biscotti expanded outside North Beach Italian bakeries and gained mass appeal in the 1980s when Bonnie Tempesta and her mother started selling them in grocery and specialty stores under the name La Tempesta Biscotti.

As a relatively new pastry chef, I remember touring their bakery and being impressed with the simplicity of the kitchen. Three double convection ovens, a couple of mixers and a few wooden tables were all that was needed to crank out hundreds of thousands of biscotti a day.

Bonnie Tempesta no longer owns La Tempesta, but she has a new biscotti company called Boncora, and the cookies are as good as her original ones.

Traditional biscotti were made with almonds, but American pastry chefs have been creatively adapting them for years, incorporating dried cranberries and white chocolate, sour cherries and pecans, macadamia nuts and orange zest, pecans and dark chocolate.

You can do the same at home, adapting a recipe to use various nuts and dried fruits. Just remember to keep the amount of the add-ins the same.

In the accompanying version, I use brown sugar and espresso to give them a deeper taste. The cocoa nibs and almonds provide added hits of flavor.

The secret to biscotti is the second bake. For the first bake, the dough is rolled into logs and baked until firm. Then they’re sliced on a slight diagonal and baked at a slightly lower temperature to dry them out and make them crunchy.

You can make mini biscotti by dividing the dough into quarters and then rolling the quarters out into the same 12-inch log. Because the volume is less, they won’t take as long to bake. Then slice them one-fourth-inch thick. I like them this size to garnish bowls of homemade ice cream.

For added crunch I coarsely grind biscotti in a food processor and sprinkle them on top of a trifle or the sides of a whipped cream cake.

Because biscotti, unlike other cookies, stay fresh longer, you don’t have to worry about eating them all the day or two after you bake them before they get stale. You can savor them slowly.

Chocolate Biscotti

Makes about 40

One side of the biscotti gets a coating of chocolate and a scattering of cocoa nibs. Melt the chocolate by barely heating it so it remains shiny and “in temper.”

• 2 large eggs
• 1/2 teaspoon vanilla extract
• 1 cup all-purpose flour + more for dusting
• 1/3 cup cocoa powder, Dutch process or natural
• 1 teaspoon baking soda
• 1/8 teaspoon kosher salt
• 1/3 cup granulated sugar
• 1/3 cup firmly packed light brown sugar
• 1 1/2 teaspoons instant espresso or instant coffee
• 1/4 cup coarsely chopped whole toasted, unsalted almonds
• 1/2 cup cocoa nibs
• 5 ounces finely chopped bittersweet chocolate, 68%-72% cacao preferred

Instructions: Preheat the oven to 350°. Line a rimmed baking sheet with parchment.

Whisk together the eggs and vanilla extract together in a small bowl; set aside.

In another bowl, combine the flour, cocoa powder, baking soda, salt, sugars, espresso, almonds and 1/4 cup of the cocoa nibs until thoroughly blended.

Add the eggs and vanilla. Mix until the dough comes together evenly.

Divide the dough in half. Dust your work surface with flour and roll each piece of dough into a 12-inch log. The dough is soft so it won’t take much pressure to roll. If the dough sticks to the counter or your hands, add more flour.

Transfer logs to the prepared baking sheet. Bake until the logs are firm, about 15 minutes. Remove the baking sheet from the oven and decrease the oven temperature to 300°.

Let the logs cool to room temperature. Slice on a slight diagonal 1/2-inch thick and about 3 inches long.

Place the biscotti – cut side up – back on the baking sheet. Bake another 12-15 minutes to dry them out. Let cool on a rack; they will crisp as they cool.

Warm the chocolate in the microwave in 10- to 15-second increments. Or, melt the chocolate in a bowl over water that has been brought to a boil, then taken off the heat -stirring frequently – just until melted.

Use a small offset spatula or a knife to spread a thin layer of chocolate on a cut side of each biscotti, and place, chocolate side up, on a second rimmed baking sheet. Working in batches, sprinkle the biscotti with some of the remaining cocoa nibs, which will stick as the chocolate sets.

Let the chocolate set before serving. Store the biscotti up to 2 weeks in an airtight container.

Per biscotti:
55 calories, 1 g protein, 9 g carbohydrate, 2 g fat (1 g saturated), 11 mg cholesterol, 41 mg sodium, 0 g fiber.

Emily Luchetti is the executive pastry chef at Waterbar and Farallon in San Francisco, the author of several baking books, and the winner of the best pastry chef award from the James Beard Foundation. E-mail: food@sfchronicle.com