Christmas Baking
Swiss Meringue Buttercream: Silky and Stable Enough to Pipe Christmas Cakes and Cupcakes
Silky, stable Swiss meringue buttercream made with cooked egg whites, sugar and butter.
Instructions
Set up a double boiler: bring a small amount of water to a simmer in a pot.
Put the egg whites and sugar in a stainless steel or glass bowl.
Set the bowl over the steam (the bottom must not touch the water). Whisk for 3 to 5 minutes. The mixture must reach 131 to 140°F (55 to 60°C) so the whites are heated through.
The sugar must dissolve completely (check by rubbing a little between your fingers).
Pour the hot mixture into the bowl of a stand mixer. Whip at medium-high speed until you have a stiff, glossy meringue.
The bowl with the meringue must cool completely to room temperature. This is key!
Reduce the mixer speed to low. Add the softened butter a cube at a time. It must be the same temperature as the meringue.
CRITICAL STEP: At this stage the buttercream will almost certainly change texture. It can look curdled, thin or like scrambled eggs. This is normal!
KEEP WHIPPING! Raise the speed and continue beating, even for 5 to 10 minutes. The buttercream will come back together into a perfectly smooth, firm emulsion.
Finally add the vanilla and mix briefly. The buttercream is ready.
- If the buttercream looks curdled or like scrambled eggs, keep whipping; it will come together. If it is too soft (the butter was warm), chill the bowl for 5 minutes and whip again. If it is lumpy (the butter was cold), warm the side of the bowl briefly with a hair dryer or over steam, then whip immediately.
- Warm the whites to at least 140°F (60°C) for the safest result, or use pasteurized egg whites.