Does anybody have any tips for cleaning the inside roof of an oven? My double oven is so small that a large chicken practically touches the roof and consequently the roof is thick with crud and so belches out black smoke when the door is open. Spray oven cleaners are no good as you can't spray upwards. I've tried paint stripper and caustic soda. Years ago I had a cooker with a roof that slid out for cleaning - has anybody come across a cooker like this recently? I'm due a new oven soon so does anybody know of an oven that has catalytic lining over the roof? My current one has this lining but only at the sides which is pretty useless