Winter Wonder Bars 
Makes 16 bars

12 ounces white chocolate
4 ounces bittersweet chocolate
1 1/2 cups all-purpose flour
1/2 teaspoon baking powder
1/8 teaspoon salt
10 tablespoons unsalted butter
3/4 cup white sugar
3 eggs
3 teaspoons vanilla extract
3/4 cup chopped macadamia nuts, toasted
                   
1. Preheat the oven to 325 degrees F. Grease a 9" square pan.
   Line the bottom of the pan with parchment paper. 
2. Chop 1/2 of the white chocolate into very small pieces.
   Chop the remaining white chocolate and the bittersweet
   chocolate into large chunks, set aside. 
3. Sift together the flour, baking powder and salt. Melt the
   butter in a small saucepan. Do not allow the butter to
   bubble or to color. Remove from the heat and in the finely
   chopped white chocolate. DO NOT STIR the chocolate in, set
   aside. 
4. Beat the sugar, eggs and vanilla together until thick and
   lemon colored, about 5 mins. Lower the mixer speed and add
   the butter mixture. Mix just to blend. Add the flour mixture
   and mix just until the flour is mixed in. Use a rubber spatula
   to fold in the two chocolates and the nuts. Scrape the batter
   into the pan. 
5. Bake at 325 degrees F until the brownies are just set, about
   30 mins. A toothpick inserted in the center should come out
   with moist crumbs still attached. As with all brownies it
   is better to underbake than to overbake. Allow to cool about
   1 hour then cut into squares.