1 21.5 oz package brownie mix plus eggs, water, and oil as package directs (for homemade brownies, see recipe suggestions below)
Penuche Frosting
1/2 cup chopped pecans, toasted
1/2 cup evaporated milk or light cream
5 tablespoons butter
1 1/2 cups light brown sugar, packed
1/2 cup chopped pecans, toasted*
1 1/2 cups confectioners’ sugar
1 teaspoon vanilla
Instructions
Bake the brownies in a greased and floured 9-by-13-by-2-inch baking pan following the package directions. Transfer to a rack to cool completely.
Put the chopped pecans in a dry skillet over medium heat. Cook, stirring and turning, until the pecans are lightly brown and aromatic.
In a medium saucepan, combine the evaporated milk or cream, butter, and brown sugar. Cook over medium heat, stirring, until the mixture comes to a boil. Continue boiling, stirring constantly, for 1 full minute. Remove from the heat and stir in the pecans, confectioners sugar, and vanilla. Let the mixture cool for 5 minutes, stirring about once every minute.
Spread the frosting over the completely cooled brownies. Let stand for about 45 minutes, or until the frosting is set.