Step 1

Melt the chocolate in a double boiler or use the microwave. Microwave in 20 second increments, stirring after each until completely melted. Set aside to slightly cool (so it doesn’t melt the butter or cook the eggs!).

Step 2

Whisk the flour, cocoa powder, baking powder, and salt together. Set aside.

Step 3

In a large bowl using a handheld or stand mixer fitted with a paddle attachment, beat the butter, brown sugar, and granulated sugar together on medium-high speed until smooth and creamy, about 2 minutes. Add the eggs and vanilla extract, and beat on high speed until combined, about 1 minute. Scrape down the sides and up the bottom of the bowl and beat again as needed to combine. Pour in the slightly cooled melted chocolate and mix on medium speed until combined.

Step 4

On low speed, add the dry ingredients. Turn the mixer up to medium-high speed and beat until combined. Finally, beat in the walnuts and chocolate chips. Cover and chill the dough for at least 45-60 minutes in the refrigerator (and up to 4 days). If chilling for longer than a few hours, allow to sit at room temperature for at least 30 minutes before rolling and baking because the dough will be quite hard.

Step 5

Preheat oven to 350°F (177°C). Line baking sheets with parchment paper or silicone baking mats.

Step 6

Roll the dough into balls, about 1.5 Tablespoons of dough each. Place 3 inches apart on the baking sheets and bake for 11-12 minutes or until the edges appear set. The centers will look a little soft.

Step 7

Remove from the oven and allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely. While the cookies are still warm, I like to press a few more chocolate chips or walnut pieces into the tops– this is only for looks!