Line large baking sheets with unbleached parchment paper and set aside.

In a large mixing bowl, place the oats and cocoa powder, and toss to combine. Set the bowl aside.

In a medium-size, heavy-bottom saucepan, place the butter, sugar, milk, and salt. Whisking frequently, bring the mixture to a rolling boil over medium-high heat.

The mixture will bubble quite a lot. Just continue to whisk. Allow the mixture to boil for a full 2 minutes, whisking frequently.

Remove the saucepan from the heat, add the chopped chocolate and mix until the chocolate is melted, and the mixture is smooth.

Create a well in the center of the oats in the large bowl and pour in the sugar mixture. Mix to combine well.

The mixture will be thick but soft. Allow it to sit at room temperature for 5 to 10 minutes to allow it to begin to firm up.

Using a large ice cream scoop or two spoons, scoop the cookie dough in 2 tablespoon portions onto the prepared baking sheets, about 1-inch apart from one another. Spread each gently into an approximately 2-inch round.

Allow the cookies to set at room temperature or in the refrigerator. After about 30 minutes, you should be able to peel them off the parchment paper.

Store the finished cookies in a sealed glass container at room temperature or in the refrigerator.