Dark Chocolate Cake with Chocolate Orange Ganache and Orange Buttercream

So it's a bit of a ridiculously long title, but it's a review of this recipe from the yellow Gourmet cookbook, so I thought I'd keep the name.  I've been looking at this cake for years now and finally got around to making it.

I made the cake and ganache as directed, and adapted the buttercream a bit.  I'd made the lemon raspberry wedding cake from the same cookbook a couple years ago, and I thought the buttercream was very heavy, so just lightened it a bit.  I made the orange curd as directed, and then added half the curd to swiss meringue buttercream with one less stick butter than usual (4 whites, 1/2 c sugar, 2 sticks butter). 

The buttercream was perfect - not too over-the-top orangey, and not too dense and heavy (leaving out the extra stick butter).  The cake itself was tender and fine, nice and chocolaty, not too dense or light or crumbly.  The orange ganache was my favorite element, though.  I'm thinking of trying some truffles with the ganache.  Altogether we really liked this cake - rich dark chocolate brightened with a little orange.  This is a new grown-up favorite!