Could one make this in a muffin tin instead of a cake pan?

I imagine you could, because cupcakes are basically nothing but small cakes. The one challenge would be the type of muffin pan you used. If you use a typical 12 muffin pan, those in the center would bake more slowly than those on the outside and that might lead to trouble with outside cakes over baking slightly. I'd also recommend using cupcake liners, so they are easier to remove after cooling. If you spray the paper liners before filling them, they generally come away easily and cleanly.