Preheat the oven to 350 degrees.  Grease a 9-inch square baking pan and line the bottom of the pan with parchment paper.  Allow the paper to extend over the sides to make the brownies easier to remove.  Set aside.

In a medium bowl, whisk together the flour, dark cocoa powder, espresso powder, and salt.  Set aside.

In a large glass measuring cup, add ¼ cup of the chopped chocolate and the butter.  Use a microwave to melt them together, stirring after every 30-second interval.  Set aside to cool.

Meanwhile in the bowl of an electric mixer on medium speed, beat together the brown sugar, vanilla, eggs, and egg yolks until well combined and the sugar is dissolved – about 3 minutes.

Add the chocolate mixture and beat until just combined – about 1 minute.

Spoon in half of the flour mixture and beat until just combined.

Pour in the stout, mix in, and then add the remaining flour.  Beat until well mixed.

Fold in the remaining chocolate and the raspberries by hand.

Spread the batter into the prepared pan.

Bake in the preheated oven for 35 minutes or until the top of the brownies looks dry and are firm when touched.  A toothpick inserted into the center will come out with moist bits of fudge, but will not look gooey.  If it looks gooey, bake it a few minutes longer. 

Cool the brownies in the pan set on a wire rack. Run a knife around the edge of the pan and use the parchment paper to lift the brownies from the pan.

Cut into squares.