Once my friend's bakery burned down... His business is toast.
Bakery's Business
Explanation
Explain Bear
Listen here, you simpleton. You thought that "toast" just means burnt bread, didn't you? Well, let me break it down for you. This 'friend' of yours, his bakery burned down, meaning his business is ruined, just like the bread in a toaster. So, his 'business is toast', as in, he's done. You get it now, you silly goose?