1. Heat oven to 350°F. Grease 13x9x2-inch baking pan.
2. Beat butter, granulated sugar and brown sugar until well blended. Add eggs, one at a time, beating well after each addition. Stir in vanilla. Stir together flour, baking powder and salt; beat into butter mixture. Stir in chocolate chips and nuts.
3. Spread half of batter (about 2-1/2 cups) in prepared pan. Spoon syrup over top; evenly spread over surface to within 1/2-inch of edge. Drop remaining batter by teaspoons over syrup so that surface is almost covered completely. (As the blondie bakes the syrup showing in the spaces between the batter will form a paisley effect.)
4. Bake 35 to 40 minutes or until lightly browned. Cool completely in pan on wire rack. Cut into bars. Makes about 24 bars.