John has written a short story about that famous composer's writing of his ever-popular 'Brandenburgs'. Here's the first paragraph.
Herr Kapellmeister Bach hummed joyfully as he left Kothen Castle, following his most agreeable audience with Prince Leopold that morning. Although his employer was of the renowned dynasty of Ascania, all formalities had been put aside as the Prince enthusiastically invited his esteemed friend to sample the exotic refreshment of Turkish coffee, a delectation which had lately been finding its way, and with some celebration, into the royal courts of Europe. "Bring me coffee, before I turn into a goat!" he had even risked saying to the Prince, reviving one of their favourite jokes.