I've never had the nerve...just put a lentil soup in, we're going out in 2 hours and ideally want it in 4 hours so I either need to leave it on for the 2 hours we're going to be out or it'll be raw...it's been on high for 30 mins and the slab of butter I put right at the bottom still hasn't melted so it isn't exactly hot but I do worry about a thick soup drying out and possibly burning.