Heat oven to 350 degrees F. Line a 13 x 9 x 2-inch baking pan with nonstick foil.Advertisement
Combine chocolate and butter in a medium-size saucepan. Heat over medium heat, stirring, until chocolate is melted and mixture is smooth, about 4 minutes. Let cool slightly.
Stir in sugar, walnuts and salt. Stir in eggs, one at a time. Stir in 1/2 cup of the mini chips, the flour and the vanilla. Pour into prepared pan. Sprinkle top with the remaining 1/4 cup mini chips.
Bake at 350 degrees F for 35 minutes or until brownie is dry on top. Cool in pan on wire rack for 10 minutes, then use foil to lift brownie from pan. Cool, then dust with confectioners' sugar, if desired.