There are 3 pancakes in a hat: one is golden on both sides, one is brown on both sides, and one is golden on one side and brown on the other. You reach in, pull out a pancake, plop it on the table, and the side you can see is golden. What's the probability that the other side is also golden?

This market resolves to that probability.

(We'll determine this by consensus in the comments, which I'm confident we will achieve this time because this problem is completely straightforward. We can simulate it to convince people if needed! I won't trade in this market so I can be a disinterested adjudicator juuuuust in case consensus proves tricky.)