Preheat oven to 350 degrees F. Grease a 9x13 inch pan.
Place butter and chocolate in a bowl and microwave in 30 second increments until melted. Whisk in sugar, eggs, and vanilla until smooth. Add flour, soda, and salt and stir until combined. Pour into pan and smooth even. Bake 23-25 minutes until toothpick comes out clean. Meanwhile, make the frosting.
For the Frosting:
Place milk, sugar, butter, and egg yolks in a 3 quart saucepan. Cook over medium heat whisking continuously until bubbly, 13-15 minutes. Stir in pecans and coconut and cook 2 more minutes. Remove from heat and stir in vanilla. Spread over warm brownies. Cool to room temperature and serve.
German Chocolate Brownies https://www.garnishandglaze.com/german-chocolate-brownies/