Sweet and Salty Pretzel Brownies

You'll need a 9-in. square baking pan lined with nonstick foil to extend about 2 in. above opposite ends of pan. Melt both chocolates and the butter in a large bowl in microwave or in a heavy saucepan over medium-low heat, stirring often, until blended and smooth. Remove from heat; stir in cracker crumbs (you should have 2 cups) and milk until blended. Fold in 2 cups pretzels. Spread evenly in prepared pan. Lay remaining pretzels on top. Cover and refrigerate at least 1 1/2 hours or until firm. Lift foil by ends onto cutting board. Cut into 6 strips, then cut each strip into 6 squares.