Heat butter in saucepan until it is a light brown color. Remove from heat. Add syrup, cream and sugar to the saucepan. Mix and frost blondies.
Preheat oven to 350°F. Sift together flour, baking powder and salt. Set aside. In a large bowl combine butter, egg, and sugar until well blended. Stir in syrup and flour mixture. Add nuts and spread 1/2 dough into 9 inch square pan. Mix blackberry jam with lemon rind and lemon juice. Drop jam mixture in six places over the dough. Carefully spread the remaining dough on top. With a knife, swirl through the dough in two directions, making a ribbon design. Bake for 30 minutes, or until toothpick comes out clean. Frost with caramel icing after cooling.
2 dozen bar cookies