Ralph Fiennes invites a group of diners to savour his cuisine. Or rather: He orders them to. Starring in the dark US satire “The Menu” as the arrogant chef Slowik, the British actor announces each of his gourmet creations with a thunderous hand clap, no matter how absurd they may be. The menu includes artfully draped strands of seaweed, sea foam that is supposed to “melt in your mouth” as a delicacy, a “breadless bread plate” – as well as increasingly shocking, murderous surprise courses. It soon becomes clear that anyone who makes it to dessert will be lucky. With “The Menu,” British director…