I do this in a pan in my convection oven - 350 degrees for about 40 mins!
Do you mix the butter in when you do it in the oven?
4 hours!!!! To cook a cake that would take 40 mins tops in an oven!!!Why?????
maybe because of the amount of hydro the cake takes if its in the oven... in the crock pot it is hardly any hydro even after 4 hours .... ? or maybe you are cooking something else in the oven..... that would be my guess