Peanut Butter Pretzel Brownies

1 pound unsalted butter
1 pound plus 12 ounces semisweet chocolate chips [I used 24 ounces dark chocolate chips.]
6 ounces unsweetened chocolate
6 extra-large eggs
2 Tablespoons pure vanilla extract
2 1/4 cups sugar
1 cup all-purpose flour
1 Tablespoon baking powder
1 teaspoon salt

Preheat the oven to 350 degrees.
Butter and flour a 12x18x1-inch baking sheet. [I used Bakers Joy Original No Stick Baking Spray with Flour.]
Melt together the butter, 24 ounces chocolate chips, and the unsweetened chocolate in a medium bowl over simmering water. Allow to cool slightly. In a large bowl, stir (do not beat) together the eggs, vanilla, and sugar. Stir the warm chocolate mixture into the egg mixture and allow to cool to room temperature.
In a medium bowl, sift together 1 cup of flour, the baking powder, and salt. Add to the cooled chocolate mixture. Pour into the baking sheet.
Bake for 20 minutes, then rap the baking sheet against the oven shelf to force the air to escape from between the pan and the brownie dough. Bake for about 15 minutes, until a toothpick comes out clean. Do not overbake! Allow to cool thoroughly, refrigerate, and cut into 20 large squares.

Source: This is a modification of Ina Gardner's Outrageous Brownies Recipe from Foodnetwork.com

I topped the Brownies with:
Peanut Butter Frosting
1/2 cup (1 stick) unsalted butter, softened to room temperature
1 cup creamy peanut butter
1-2 cups confectioners' sugar

Source: http://sallysbakingaddiction.com/2012/07/09/chocolate-covered-pretzel-peanut-butter-brownies/

And then I topped it all off with Flipz Chocolate Covered Pretzels

Submitted by Amy A.