<b> For the Blondies</b>
Preheat the oven to 350 degrees F.
Stir brown sugar and melted butter together. Add egg and vanilla. Mix well.
Stir in salt, baking powder, and baking /soda. Gradually add flour a little at a time. Stir until just combined.
Fold in white chocolate chips and chopped walnuts.
Evenly spread batter into a greased 9x9 inch pan lined with foil.
Bake 20-25 minutes or until a toothpick inserted in the center comes out with just crumbs.
<b> For the Maple Butter Sauce </b>
In a medium saucepan, melt butter over medium heat. Stir in maple syrup and brown sugar. Stir constantly until sugar is dissolved. Fold in walnuts.
Serve blondies topped with maple butter sauce and a scoop of vanilla ice cream if desired.