1/2 cup + 2 Tbsp flour
3 Tbsp unsweetened cocoa powder
1/4 tsp salt
1 cup sugar
5 Tbsp butter, room temperature
1-1/2 tsp vanilla
1 cup chocolate chips
1. Preheat to 350°F. Line 2 large rimmed baking sheets with parchment paper.
2. Melt bittersweet chocolate in double boiler. Cool melted chocolate 10 minutes.
3. Meanwhile, sift flour, cocoa powder, baking powder, and salt into medium bowl. Using electric mixer, beat sugar and butter in another medium bowl until crumbly. Add eggs, 1 at a time, beating well after each addition. Continue to beat until mixture is light, pale, and creamy, about 5 minutes.
4. Add lukewarm melted chocolate and vanilla and beat just until blended. Fold in dry ingredients, then chocolate chips.
5. Drop chocolate cookie batter by 1/4 cupfuls onto prepared baking sheets, spacing 2 inches apart. Bake cookies, 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. Using metal spatula, carefully transfer 4 cookies to each of 4 large resealable plastic bags. Freeze.