As an April Fool’s joke, the British Library posted this story about the finding of a rare unicorn cook book. I have yet to find instructions for cooking mythical creatures in the Kirschner Collection (which is not to say that they don’t exist), but we do have the Hippo Cook Book:

This book, published in 1969, is full of recipes from San Francisco’s Hippopotomus Hamburger Restaurant. As you can see from the menu, this place was serious about creative hamburgers — you’ll find such recipes as The Cannibalburger (aka Steak Tartare), The Kyotoburger, and The Bourbonburger in the book. Also, nearly every page is accompanied by a cute, clever illustration from artist Wolo von Trutzschler, the restaurant’s signature artist. Here is Wolo’s take on The Stanfordburger: