How to Make It
Prepare brownie mix according to package instructions. Cool for 20 minutes.
Combine evaporated milk, sugar, egg yolks, butter, and vanilla in a stand mixer and beat on low until evenly blended. Transfer to a medium saucepan. Cook over medium heat, stirring constantly, until frosting starts to bubble and has a rich caramel color, about 12 minutes, then cook for 10 minutes.
Stir in coconut flakes and pecans. Remove from heat and cool until thick enough to spread, stirring occasionally.
Spread the frosting evenly over cooled brownies with a silicone spatula. Let the frosted brownies stand for a few minutes before serving.