I love black garlic and am never without it. I get it both from regular multi-cloved garlic and from the local single head garlic.
I use it mostly simply as a replacement for regular garlic but particularly like it with pasta. I add it to pesto, too. And I consider my black garlic risotto to be a winner.
You can mash it into mayo and use that as you prefer.
But a personal favourite is this stir fried chicken with black garlic, here served with orzo.
When I had a second home in the countryside, I used to blacken garlic myself, but my neighbours in the city wouldn't thank me for trying that here, so now I buy it from the store.