⅓ cup cocoa powder

½ cup plus 2 tablespoons boiling water

2 ounces unsweetened chocolate, finely chopped

2 large eggs

2 large egg yolks

1 teaspoon vanilla extract

2½ cups sugar

1¾ cups all-purpose flour

¾ teaspoon kosher salt

2½ ounces bittersweet chocolate, coarsely chopped

2 cups shredded sweetened coconut

Fleur de sel, for sprinkling

1. Heat the oven to 350 degrees. Lightly grease a 9-by-13-inch baking pan.

2. In a large bowl, whisk together the cocoa powder and ½ cup plus 2 tablespoons boiling water until smooth. Add the unsweetened chocolate and whisk until the chocolate has melted. Whisk in the olive oil. Add the eggs, yolks and vanilla, and continue to whisk until combined. Add the sugar, whisking until fully incorporated. Using a spatula, fold in the flour and salt until just combined. Fold in the bittersweet chocolate pieces.

3. Pour half the batter into the prepared pan and smooth with a spatula. Sprinkle 1 cup of the shredded coconut on top of the batter. Pour in the remaining batter and smooth. Top with remaining coconut. Sprinkle with fleur de sel and bake until just set and firm to the touch, about 25 to 30 minutes. (These brownies solidify as they cool, so inserting a toothpick to check for doneness will not work; it will not come out clean.) Transfer the pan to a wire rack and allow to cool completely before cutting into 2-inch squares.

The book’s binding was crafted out of dark, fine-grained calfskin, its richly tooled embossings age-mellowed to the color of . . .

“Chocolate,” murmured Arianna Hadley. Removing her gloves, which were still sticky from foraging through the food stalls at Covent Garden, she traced the delicate leaf design centered beneath the gilded title. “How lovely,” she added, and then carefully opened the cover.