When Katherine, at the Sweetfest, mentioned that her swiss meringue buttercream recipe was from Martha Stewart, I wondered whether my Martha Stewart’s CAKES would have the recipe. And it did. And then we were invited to a friend’s house, and I had banana and walnut cake in the freezer already, and so… experiment! (Of course, it’s also online.)
Stewart’s version makes 9 cups’ worth and requires a swoon-worthy amount of eggs and sugar. So I’ve written the halved ingredients into the book itself, and then I realised that I only had 150g of butter anyway so I just figured out how much sugar and so on that required; the answer was 2 whites, and so on.
It’s a very straightforward process to make the frosting, happily. Yes there’s whisking of sugar and whites, but that didn’t take too long. The rest of the process was easy.
I didn’t flavour the buttercream aside from the vanilla, since it was going on a banana cake anyway. It was easy to spread onto the cake, which is an important thing for me. I had enough left over that I could have frosted the edges if I wanted, but decided that that would be a bit of overkill – especially when I discovered that the buttercream will last in the freezer for three months. So into a jar it goes. No idea where it will be used in the future.