substitute for vegetable oil

Hi Hannah! I answered on the recipe page - I haven't tried butter, but it should work. Just melt it , so the batter consistency will be the same. Let us know how it turns out!! I have another similar recipe on the site, which is quite possibly my favorite cake in the world, and not vegan. It's cupcakes, but you can totally make it in cake pans, which I do from time to time. https://food52.com/recipes/2899-chocolate-stout-cupcakes

You can try butter in the same proportion, or coconut oil. But it will likely turn out a bit different. However, you won't know til you experiment a bit. I'd say, coconut oil is more likely to give you a much similar result. But that's just a "thought". Try it and see :)