All you need to do is cover the tin with foil. It will steam the centre of the cake. Don't fret pet xxx
I was meant to bake for 40mins ... has so far been in an extra 15mins and i have just put some foil over it as you suggested

... sad thing is it looks absolutely fantastic (beautifully high) but i can't see it but can smell that it's burning (maybe underneath or/and sides)