Lynne is cooking. She tells George that the vicar called round and tried her cooking. George asks if he liked it and Lynne replies that he did and that he said only one thing was stopping her becoming one of those TV cooks. George asks what that was and Lynne replies it is her sexy revealing outfits like this. George lets out an 'Oh, Lord.'
The vicar has a habit of turning up at people's houses unannounced. In this case he arrived at lunchtime, knowing full well that both Lynne would be preparing lunch and George would be at work. The vicar knows women will always let him in and therefore he gets free lunches every week day.
Although the vicar says that Lynne's revealing sexy items are holding her back in her quest to become a TV cook, they could in fact be her selling point. At this point in time she would be up against Fanny Cradock's Thatcher-esque face or Keith Floyd's boozy lunches. Her mix of sex and cooking could send her on a one way ticket to stardom.
The one thing that is really holding her back is that she doesn't work in food, and that she doesn't have a book deal. George knows more. His 'Oh, Lord' is an excellently worded response to the vicar's unashamed flirting. The vicar is known for this too and it is now getting out of hand. It's either that or it was Sammy in a vicar's outfit.