How To make Chocolate Chunk Brownies

1 1/4 c All-purpose flour
1/4 ts Baking soda
1/8 ts Double acting baking powder
1/8 ts Salt
14 oz Semisweet chocolate

Finely chopped 1 c Granulated sugar
9 tb Unsalted butter :

cut
Tablespoons 1/4 c Light corn syrup
1/4 c Water
3 lg Eggs

chilled
1 tb Vanilla extract
1 1/2 c Coarsely chopped walnut :

Halves, divided 9 oz Swiss dark chocolate

cut
Inch chunks :

divided
Position a rack in the center of the oven and preheat to 325 degrees F. Line a 13-by-9 1/2-inch baking pan with a double thickness of aluminum foil so that the foil extends 2 inches beyond the two short ends of the pan. Fold the overhang down along the sides of the pan. Butter the bottom of the foil-lined pan. In a medium bowl, stir together the flour, baking soda, baking powder and salt. Place the semisweet chocolate in a large bowl. In a medium saucepan, combine the sugar, butter, corn syrup and water. Cook over medium heat, stirring constantly with a wooden spoon, until the butter melts, the sugar is dissolved and the mixture comes to a boil. Remove the pan from the heat and pour the hot syrup over the chocolate. Let the mixture stand for 1 to 2 minutes, to melt the chocolate. Whisk until smooth. One at a time, whisk in the eggs, blending until smooth. Whisk in the vanilla and the flour mixture, mixing until the batter is smooth. Using a rubber spatula, fold in 1 cup of the walnuts and 6 ounces of the Swiss chocolate chunks. Scrape the batter into the prepared pan and spread it evenly with a spatula. Sprinkle the remaining 1/2 cup of walnuts and 3 ounces of chocolate chunks over the top of the batter. Bake the brownies for 40 to 50 minutes, or until a cake tester or toothpick inserted into the center of the brownie comes out with a few moist crumbs clinging to it. Cool the brownies in the pan set on a wire rack. When the brownies are completely cool, cover the pan of brownies with plastic wrap and let the brownies set at room temperature for at least 6 hours or overnight. Invert the brownies onto a large plate or cutting board. Remove the pan and carefully peel off the foil. Invert again onto a smooth cutting surface and cut into 24 bars. Store the brownies at room temperature in an airtight container for up to five days. Recipe By :