So, while of course there are many widely known and available tiramisu recipes, a specific recipe from a specific restaurant is not necessarily so. Just in passing, this is something that many people who wish for an end to software copyright forget: the alternative to copyright is not at all free public software, it is trade secret Linux "recipes".
Now to get back to the tiramisu part, I think what makes it delicious in some restaurant is either obfuscated (e.g. the chef has a specific way to process some of the steps, or use some benign undisclosed ingredient). Or it's based on a specific ingredient that won't be available to anyone seeking it. For instance the coffee they use come from the chef's own farm, or they grind it a specific way that only works with their machinery as they haven't gone public about it.
In many ways I think the generic recipe of most games is widely available: if we gave you a team and a few billion dollars, you could probably make a generic Fortnite clone in less than a year. But would it be as good as what Epic's team is providing right now ? probably not ? (no offence)