bread
One of the things that keeps me messing around with breadmaking (albeit with a machine, which makes devotees of True Artisanal Handmade Bread regard me as a baby or a dilletante, but, hey, I used a biga starter a couple of times) is that every loaf comes out different. The flour/water mix has to be just right, and the correct can be affected by such things as the local humidity. So you never quite know if the thing is going to overrise and crater, or not rise enough. Unless you are a bread god.