Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking pan, or line it with parchment paper for easy removal later.
In a large bowl, beat 4 eggs together with cocoa powder, salt, baking powder, espresso powder (if using), and vanilla extract until smooth and well combined.
In a separate bowl, melt your butter in the microwave or on the stove. Once melted, stir in the sugar until fully mixed. The warm butter will help dissolve the sugar, creating a smooth texture.
Add the butter and sugar mixture into the egg and cocoa mixture, stirring gently until fully combined.
Sift in your flour and stir in the chocolate chips until the batter is smooth and well mixed.
Transfer the batter to the prepared pan and smooth it out evenly. Bake for 30 to 40 minutes, checking with a toothpick. Your brownies are ready when a toothpick comes out with just a few moist crumbs!
For a gooey center, check around 30 minutes; for firmer brownies, let them bake a little longer.
Allow the brownies to cool in the pan on a wire rack for that perfect fudgy texture.
Meanwhile, prepare the frosting: In a medium saucepan, combine salted butter, brown sugar, egg yolks, and evaporated milk.
Cook over medium-low heat, whisking often, until well combined.
Increase the heat to medium, bring it to a boil, and whisk until it thickens, about 5 minutes.
Once thickened, remove from heat and stir in vanilla extract, toasted pecans, and shredded coconut.
Once the brownies are completely cool, spread the coconut pecan frosting on top, slice into squares, and serve!
Enjoy your delicious German chocolate brownies!