Am I the only one that thinks the best part about cake is the icing!? I only eat the cake for the icing and it's even better with DONA chai concentrate! Why not make your sweet icing a little spicy ;)
- Bring a saucepan filled with about 2 inches of water to a simmer. Meanwhile, combine sugar, egg whites, and salt in a large heatproof mixing bowl. Set bowl over (not in) pan of simmering water and whisk until whites are warm to the touch and sugar has dissolved, 2 to 3 minutes. (Test by rubbing between your fingers; mixture should feel smooth.)
- Attach bowl to mixer fitted with the whisk attachment; beat on medium-high speed until stiff, glossy peaks form and mixture has cooled completely, about 12 minutes.
Reduce speed to medium-low; add butter, 2 tablespoons at a time, beating to incorporate fully after each addition. (Don't worry if buttercream appears curdled at this point; it will become perfectly smooth again with continued beating.) Beat in chai concentrate.
Switch to paddle attachment and beat on lowest speed to remove air bubbles, 3 to 5 minutes. If using buttercream the same day, cover bowl with plastic wrap and let stand at room temperature until ready to use.