In a small saucepan over medium heat, melt the butter. Continue cooking, stirring often, until the butter foams and then darkens slightly in color and becomes very fragrant, 4–6 minutes. Immediately pour the butter into a large heatproof bowl. Do not wash the pan.
In the saucepan used for the butter, add the red wine and two tablespoons of granulated sugar and bring to a simmer over high heat. Reduce the heat to medium and simmer, stirring occasionally, until reduced to 1/3 cup, approximately 16–18 minutes. Pour the reduced wine into the bowl with the butter and let the mixture cool for 15 minutes.
Meanwhile, whisk the flour, cocoa powder, baking powder, baking soda and salt in a medium bowl. Preheat the oven to 350°F and set two racks at the upper-middle and lower-middle positions. Line up to three baking sheets with parchment paper.
Whisk the brown sugar and remaining 1/3 cup of granulated sugar into the butter-wine mixture, and then whisk in the eggs and vanilla extract until smooth. Stir in the flour mixture with a spatula until a soft dough forms, then stir in the chopped chocolate.
Use your hands to roll the dough into 1/4-cup-sized balls and drop onto the prepared baking sheets at least three inches apart.
Bake two sheets at the same time, swapping the top sheet to the bottom rack and the bottom sheet to the top midway through baking, for a total of 11 to 14 minutes, or until the tops of the cookies are lightly cracked, and then bake the remaining cookies. Let cool completely on the baking sheets. Store in airtight container for up to one week.
