Makes 24 large cookies
- 3/4 cup plus 2 tablespoons cake flour
- 1 tablespoon baking powder
- 1/8 teaspoon kosher salt
- 1 tablespoon powdered instant coffee
- 1 tablespoon boiling water
- 1 teaspoon vanilla extract
- 7 oz unsweetened chocolate, coarsely chopped
- 6 oz bittersweet chocolate, coarsely chopped
- 8 tablespoons (1 stick) unsalted butter
- 7 large eggs
- 2 3/4 cups sugar
- 2 cups chopped walnuts
- 1 1/2 cups chocolate chips
- Preheat the oven to 350°F. Line two baking sheets with parchment paper.
- Sift the flour, baking powder, and salt into a bowl and set aside. Combine the instant coffee and boiling water to make a paste. Blend in the vanilla extract.
- Melt the unsweetened chocolate, chopped bittersweet chocolate, and the butter in a saucepan over low heat or in a bowl in the microwave in 15- to 20-second intervals. Gently stir to blend.
- In a stand mixer fitted with the whisk attachment, mix the eggs, sugar, and coffee paste on high speed until light in texture and thick, 6 to 8 minutes. Add the chocolate mixture with the machine running on medium speed. On low speed, mix in the dry ingredients until just blended. Mix in the walnuts and chocolate chips until blended. Scrape down the bowl as needed.
- Scoop a level, 1/4 cup of dough onto the prepared baking sheet, leaving 3 to 4 inches between the cookies. In batches, bake the cookies until they are cracked on top, but still slightly moist, about 14 minutes. Allow the cookies to cool slightly on the baking sheet before transferring to a wire racks to cool completely.