1 1/4 cup bittersweet chocolate (I just use Ghirardelli chips)
1/2 cup plus 2 teaspoons all-purpose flour
3 tablespoons unsweetened cocoa powder
1/4 teaspoon baking powder
1/8 teaspoon salt
1 cup plus 1 tablespoon finely granulated sugar
5 tablespoons butter, room temp
3 large eggs
1 1/2 teaspoons vanilla extract
1 cup chocolate chips
Position rack in center of oven and preheat to 350F. Line 2 large baking sheets with parchment paper. Stir chopped chocolate in a bowl set over simmering water until melted and smooth; remove from over water. Cool melted chocolate for 10 minutes.
Meanwhile, sift together flour, cocoa powder, baking powder and salt into a medium bowl. Using electric mixer, beat sugar and butter in another medium bowl until crumbly. Add eggs, one at a time, beating well after each addition. Continue to beat until mixture is light, pale, and creamy- about 5 minutes. Add lukewarm melted chocolate and vanilla, and beat just until blended. Fold in dry ingredients and chocolate chips.
Drop batter by 1/4 cupfuls (I use a small ice cream scooper) onto prepared baking sheets, spacing 2 inches apart. Bake cookes, 1 baking sheet at a time, until tops are evenly cracked but cookies are not yet firm to touch, about 16 minutes.
Cool cookies completely on baking sheets.