Mini Bouchon Brownies

I made these little brownies a long time ago, and they were so delicious.  They're the first thing I tried from the new Bouchon Bakery cookbook, and I was so happy with the results.  The little brownies were so moist and chocolate-y - almost like fudge.  I actually do have a bouchon pan, but I ended up making this recipe in a mini-muffin pan just because I wanted smaller treats for a party. These are really rich, so the tiny size worked well.  The only change I'd make next time is to get some Dutch process cocoa powder...although these tasted amazing, they weren't as dark in color as the real deal.

Mini Bouchon Brownies (adapted from Bouchon Bakery)
Makes 2 dozen

141 g unsalted butter, cut into chunks
50 g all-purpose flour
50 g unsweetened cocoa powder (recipe calls for Dutch-processed, but I used regular)
1/2 tsp kosher salt
75 g eggs
162 g granulated sugar
1/4 tsp ground vanilla
112 g chocolate chips

1. Place half the butter in a medium bowl.  Melt the remaining butter, and then stir the melted butter into the bowl - some unmelted bits are okay.
2. In a separate bowl, whisk together the flour, cocoa powder, and salt.
3. In the bowl of a stand mixer fitted with the whisk attachment, combine the eggs, sugar, and vanilla.  Whisk on medium-low speed until combined.  Add the butter and flour mixtures in alternating additions (flour-butter-flour-butter-flour).  Mix well to combine.
4. Fold in the chocolate chips.  Set aside at cool room temperature for ftwo hours.
5. Preheat the oven to 350 degrees.  Line mini muffin molds with papers.  Fill each paper almost all the way with brownie batter.
6. Bake about 12-15 minutes, until a tester comes out with a few moist crumbs.