Luscious German buttercream built on a brown sugar custard base is a flavorful silky smooth way to top your favorite treats. Make some today and see for yourself!
In a small heatproof bowl, whisk together ¼ cup brown sugar and the cornstarch.
Add the eggs and whisk to incorporate. Set egg mixture by stove.
In a small saucepan, stir together remaining ½ cup of brown sugar and milk. Heat over medium heat until it starts to steam and come to a low simmer, stirring frequently. Drop heat to medium-low.
Ladle about ⅓ cup of hot milk mixture into the egg mixture, whisking as you add the hot milk mixture.
Slowly pour the tempered egg mixture into the saucepan with the remaining milk, whisking vigorously as you drizzle the egg mixture in.
Cook over medium low heat until it thickens to a tight pudding consistency, stirring constantly. (Don’t panic if small lumps form as you go.)
Turn off heat and whisk vigorously until the mixture is smooth. Add 2 Tablespoons of butter and stir until incorporated.
Cover with plastic wrap, placing the plastic wrap on the surface of the custard. Chill for at least an hour but up to a couple of days before proceeding.
Place the remaining butter and chilled custard on the counter at the same time to come to room temperature.
Once the butter is softened, beat until light and fluffy. With mixer running, add the custard a couple of Tablespoons at a time until it is all incorporated.
Add vanilla and salt and beat until light and fluffy.