Preheat oven to 350°.
Line baking sheets with parchment paper.
Combine flour, baking powder, and salt in a small bowl, set aside.
Combine butter, unsweetened chocolate, and 1 ½ cups of chocolate chips in a heavy saucepan.
Cook over low heat, stirring constantly, until butter and chocolate melt.
Let cool.
With an electric mixer, beat eggs, sugar and vanilla at medium speed.
Gradually add dry ingredients to egg mixture, beating well.
Add the chocolate mixture and beat well.
Stir in remaining 1 ½ cups chocolate chips.
Scoop dough onto baking sheets 1 inch apart.
Bake for 10 minutes.
Cool 3-5 minutes on baking sheets, then transfer to wire racks to cool completely.