Brown Sugar Caramel Rum Buttercream
- Combine brown sugar and water in a small saucepan and bring to a boil. Continue to boil until sugar has reached soft-ball stage (235-240F).
- Meanwhile, place egg whites into a clean, stainless-steel mixer bowl and with the whip atachment, beat on low speed until foamy. Raise the speed to medium high and whip until stiff, but not dry.
- While the mixer is running, add your brown sugar syrup slowly into the beaten egg whites in a steady stream. continue beating on high speed until the mixture has cooled down--about 3 minutes.
- Add the softened butter 1 tablespoons at a time with the mixer running. Add vanilla and rum. Keep beating the buttercream until it is smooth and creamy.
- Please Note: After you add the soft butter, the buttercream is going to "break" meaning it will look curdled and runny. Don't worry! Keep on whipping and it will come together!.