Butterscotch and Fudge Brownies

Got this one from Quick and Simple. 

For this recipe you will need:

Directions:

1)  Preheat oven to 350°F.  Butter a 9-inch square baking pan and line with parchment paper; butter the paper.

2)  Put 1 cup chocolate chips in a heatproof bowl over a saucepan of barely simmering water; stir until melted and smooth, then set aside.  Melt the butterscotch chips the same way.

3)  Sift the flour, baking powder and salt into a bowl; set aside.  In a large bowl, with an electric mixer on medium speed, beat the butter and brown sugar until smooth.  Add eggs and vanilla; beat 1 minute more.  On low speed, add the flour mixture, mixing until just incorporated.

4)   Spoon 2 cups of the batter into a separate bowl and stir in the melted butterscotch chips.  Mix the walnuts into the butterscotch batter and scrape into the prepared pan.  Sprinkle the remaining 1 1/2 cups chocolate chips over the butterscotch batter.  Stir the melted chocolate chips into the remaining plain batter.  Drop spoonfuls of this chocolate batter over the chocolate chips; gently spread batter.

5)  Bake about 40 minutes, or until a toothpick inserted in the center comes out with just a few moist crumbs.  Cool completely in pan.  Remove from pan and cut into bars.