Step 1

Preheat the oven to 350°F. Line baking sheets with parchment paper or silicone baking mats.

Step 2

In a medium bowl, sift together the flour, cocoa powder, baking powder, and salt.

Step 3

In the bowl of an electric mixer, beat the butter, brown sugar, and granulated sugar on medium-high speed until well combined and smooth. Add the egg, egg yolk, and vanilla and beat until combined. On low speed gradually add the flour mixture. Fold in the chocolate chips with a rubber spatula.

Step 4

Using a medium spring-loaded cookie scoop, drop the dough by 1 1/2 tablespoon rounds onto the prepared baking sheets

Step 5

Bake for about 10 minutes, or until the cookies are set. Let cool on baking sheets for 10 minutes before removing the cookies to wire racks to cool completely.

Step 6

In a small saucepan set over medium heat combine the milk, sugar, egg yolk, and butter. Cook, stirring frequently, until the mixture has thickened, about 10 minutes. Remove from heat and stir in the vanilla, coconut, and pecans. Let cool until thick enough to spread on top of the cooled cookies.

Step 7

Drizzle the melted chocolate all over the cookies. Let everything set for at least 15 minutes before serving. Cookies are best served the day they're made.