ok this is the second time this has happened to me (previously I've had zero issues)....I have used the cake mix doctor sour cream white cake recipe and put the whole thing in the oven in a 9in for 35 minutes like it says...except when I take it out its liquid in the center, but cooked on the outside. What am I suddenly doing wrong?
Should I make it in two seperate pans?
Thanks for any thoughts on why this is happening!

You need to use a heating core or flower nail in the center of the pan so the middle cooks.

Are you cooking an entire box of cake mix in 1 9" round? That could be a problem. Split it into 2 pans, only half way full.

Also, depending on the type of pan, you may need to lower your temp. Dark metal pans use a lower temp (like 325) versus shiny aluminum pans at 350.

1 box of cake mix in 1 9in pan is a scary situation! I am surprised actually that the cake is not all over the bottom of your oven.

Like kger suggested, split the batter between 2 pans and if you are using dark pan drop the temp and bake longer. You should not need a heating core (i use a flower nail) in a 9 inch pan, but it would not hurt anything if you did.