- 4 ounces semisweet chocolate chopped
- 2 cups unbleached all-purpose flour
- 1 teaspoon baking powder
- ¼ teaspoon salt
- 1 cup (2 sticks) unsalted butter, at room temperature
- 2 cups packed light brown sugar
- 2 teaspoons vanilla extract
- 3 large eggs
- Position a rack in the middle of the oven. Preheat the oven to 350° F. Line two baking sheets with parchment paper.
- Put the chocolate in a heatproof container or the top of a double boiler, and place it over, but not touching, a saucepan of barely simmering water (or the bottom of the double boiler). Stir the chocolate until it is melted and smooth. Remove from the water and set aside.
- Sift the flour, baking powder, and salt into a medium bowl and set aside. In a large bowl, using an electric mixer on medium speed, beat the butter, brown sugar, and vanilla until smoothly blended, about 1 minute. Stop the mixer and scrape the sides of the bowl as needed during mixing. Add the eggs and mix until blended, about 1 minute. On low speed, add the flour mixture, mixing just until it is incorporated.
- Drop heaping tablespoons (about 3 level tablespoons each) of dough 3 inches apart onto the prepared baking sheets. Drizzle about ½ teaspoon of the melted chocolate over the top of each cookie. Using a small sharp knife, gently swirl the chocolate once or twice through the cookie to marbleize it.
- Bake the cookies one sheet at a time until the tops feel soft but set and the edges are lightly browned, about 11 minutes. Cool the cookies on the baking sheets for 10 minutes, then use a wide metal spatula to transfer them to a wire rack to cool completely.
- The cookies can be stored in a tightly covered container at room temperature for up to 4 days.