I get blisters or air bubbles under the surface of my buttercream after I have smoothed it with a warm spatula. It doesn't happen all the time, so I can't pinpoint exactly what I am doing to cause them. I always use the same recipe for buttercream. Sometimes I can pop the bubble and re-smooth. Sometimes the bubble comes back anyway - makes the buttercream look warty! What's going on? Anyone else ever have this happen and how do I get rid of the problem??

The only thing I can think of is that maybe you're over mixing your icing and putting too much air in it.
Good Luck

The only thing I can think of is that maybe you're over mixing your icing and putting too much air in it.
Good Luck

Are you icing your cake at room temp? The only time I've ever gotten air bubbles is when I iced a cold or nearly still frozen cake.

HTH, K'ly

I am icing a room temperature cake with room temp buttercream. I always mix the color into my buttercream by hand so it won't have too much air. Maybe I catch an air bubble as I am spreading the buttercream onto the cake and trap it under the surface.