1 (10- to 11-ounce) package white chocolate morsels
1 cup toasted hazelnuts, finely chopped
Preheat oven to 350 degrees. In a heavy saucepan, melt chocolate morsels, unsweetened chocolate, and butter over low heat until melted and smooth, stirring constantly. Transfer to a large mixing bowl and let cool slightly. Add eggs, sugar, and vanilla extract to the chocolate mixture, beating well to combine. Stir in flour and baking powder. Once the batter is smooth, add white chocolate morsels and hazelnuts, stirring to distribute them evenly through the batter.
Drop dough by the heaping teaspoonful onto a lightly greased cookie sheet. Bake 8 to 10 minutes, or until the edges are firm and the surface is dull and cracked.
Cool on cookie sheet 1 minute, then remove to a rack to cool completely.