1. Heat oven to 350°F. Grease a 13 x 9 x 2-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. Combine flour, baking powder and salt and beat into butter mixture. Stir in chocolate chips and nuts.
3. Spread half of batter (about 2-1/2 cups) in the greased pan. Spoon syrup over top and evenly spread over surface 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 for 35 to 40 minutes or until lightly browned. Cool completely in the pan on wire rack. Cut into bars. About 36 bars.