Pressure Cooker. SOMEBODY WALKED AWAY FROM IT.

   Or.. didn't check the gasket first. One bit of rice stuck in
   there, and you can end up with something that seems sealed 'til
   the grain of rice puffs up and causes a gap. I believe this to
   be a 100% legit real picture. Pressure cookers are amazing
   time-savers and can do astounding things with food that other
   methods don't do as well. But... gotta know how to use 'em. Get
   past 15 PSI... and yeah, this is completely feasible. I've seen
   spaghetti sauce spray on the ceiling when someone took off the
   pressure valve. It was like a sperm whale. Ok, I was a kid and
   it was me.