I'm no expert, and I'm looking for ideas myself, but my yard cats love boiled meat broth, any meat. And if I add salt to it (once a year or so), then it's a feast. The nights are cold now, so the soup is best served warm (not hot, of course). Just make very sure no bones are left in the soup, not even tiny ones.
The Royal von Meouw Dynasty: His Royal Highness the late Prince von Meouw,
Her Royal Highness Princess Gatita von Meouw, Nikita Duchess of Meouw and
His Highness Cuchi-Cuchi, next in line for the throne of Prince von Meouw.