"A large and tasty coffee" sounds more natural to me than just "large and tasty coffee". You know, since coffee is served at shops in different sizes, "large" being one of them, I'm sure a lot of English speakers are used to hearing "a large coffee" or "a small fries" or something along those lines. Everyone seems to be complaining about it sounding unnatural, yet nobody is explaining why. So I figured I'd try my best to put it into words, lol
OK, I can agree that it's not the greatest phrase, but firstly, it's just a phrase (not even a sentence), and secondly, one of our British contributors came up with "A large and tasty coffee is on its way to you!" as an example ;) But it's more of a vocabulary + grammar exercise anyway.