Which food item is traditionally hidden inside a King's Cake during celebrations in parts of Europe?

A small figurine

What sweet food made by bees is often put on toast? Which martial art originated in Brazil focusing mainly on grappling and ground fighting? Which singer-songwriter wrote and recorded "Fast Car"? Which activist led farm-worker boycotts for better conditions in California in the 1960s and 1970s? Which inventor developed the alternating current electrical system?