Pre-heat over to 350. Line baking sheets with parchment paper.
Place butter and chocolate chips in a small saucepan and heat over medium heat until melted and smooth. Set aside.
Crack the eggs in a large mixing bowl. Add sugar and vanilla. Beat mixture for about 10 minutes until pale/creamy looking. Stir in baking powder and flour into egg mixture.
Fold in melted chocolate. Stir in butterscotch chips. Let stand for 10 minutes.
Drop batter by tablespoonfuls, about 3 inches apart. Bake 9 to 11 minutes, or they have the cracked look.
Cool on baking sheets for 10-15 minutes before moving to a wire rack to completely cool.
Recipe by Sweet Dash of Sass at http://sweetdashofsass.com/2014/12/day-10-chocolate-butterscotch-cookies/