Hi all I give my cooker a wipe over nearly every day. The top cleans easily but the inside and shelves are still mucky I have tried Mr Muscle but it's useless even using it 3 times in a row. Please can someone tell me a good cleaner it's an electric oven and as we have no gas where we live I can't change to a gas one otherwise I would as I never had this trouble with my gas oven.