Baking wasn’t something that Sirius had ever thought to learn. If they wanted a pastry or whatever, they would just go to a place that sold pastries. There was no need for flour or flavour-y liquids or berry bits. A person could buy an entire pastry, already made, straight into their hands, for only a few quid. Bing bang bosh. Remus had apparently never heard of the sorcery that was already-made pastries. Sirius tried telling him about it. 