In bed with Miranda Hart ... what fun!

I'm in a hotel bed with Miranda Hart, the nation's Best Comedy Actress, according to this year's British Comedy Awards, and star of the eponymous BBC sitcom in which she sends her- self up as an awkward, blundering, unlucky-in-love, middle-class misfit. She is semi-recumbent on the pillows, waving like the Queen and saying, 'Hello, and welcome to my suite!' From my spot next to her tanned bare feet, I can see something unexpected and utterly un-Miranda: a little ankle tattoo of a bird and a heart. 'Yuh. Peace 'n' love, man. I love my tattoo. We all got one the same.' On the occasion of your A levels? 'Embarrassingly it was a bit later than that.' In Goa? 'Oh no. In Fulham Broadway.'

Miranda is the Joyce Grenfell of the Twitter generation. Her sitcom commands four million viewers per episode because, as Jennifer Saunders puts it, 'she has funny bones'. The new guard of comedians, like Peep Show's Sophie Winkleman, also adore her: 'To be that cosy, that conventional, that brazenly middle-class,' says Sophie, 'is actually very edgy and brave.'

Incomparably arch, she can wring a laugh out of 'Hello red-button viewers and thank you for pressing'; like a classic clown, she is physically collapsible, able to auto-eject from a bar stool in the blink of an eye. She writes her own material, sending herself up as a shambolic thirty-something singleton who suffers, as in an anxiety dream, all the humiliations known to womankind: first-date farts, wrap dresses that spontaneously unwrap, and mothers who advertise one's singledom with a loud-hailer.

One suspects that Miranda, like her on- screen persona, might be a perennial singleton. ('Perennial,' she says, savouring the syllables. 'What a lovely word.' Her other favourite words, as viewers know, are 'plinth' and 'moist'.) 'Until now, I wasn't that interested. I sort of felt I didn't really need it and I was so focused on work and had lots of friends and was never really lonely.' But now things have changed? 'I've been on a few dates this year,' she says. 'I've been set up with people. It's always fairly awkward.' Where's her most romantic place in London? 'I love walking along the South Bank at night. I think I prefer sights to a restaurant. And there's the advantage that if it's not going well, you can always hail a taxi.' Is she looking for something serious? 'Maybe. I do like the idea of marriage. It's romantic. I like the idea of saying, "This is my husband" ' Would she want a church wedding? 'Oh no, that would be too formal. Someone would be bound to fall in the font. I'm not particularly into the formal, political side of faith, although I am spiritual and I do have a faith. But Strictly Come Dancing is my religion.'

She lives and breathes light entertainment. 'I'll cry at Britain's Got Talent. I do love to cry. I'll cry at the drop of a hat. I'll cry at your basic television programme, let alone a weepie. But not big, heavy, serious crying. I haven't done that for a while, which is a relief. More like a little welling up of joy.'

What sort of person is she looking for? 'Goran Ivanisevic [the Croatian 2001 Wimbledon champion]. I always used to think he was rather smashing. I'd like someone tall, dark and nice. Independent and confident. Not a macho man. Perhaps a little bit girly, in a way. The key for me is if we can cry with laughter. And Miss Peggy would have to approve.'

Miss Peggy is her adorable shih-tzu, who recently appeared with her on The Jonathan Ross Show. 'Dear Peggles. I shouldn't really have let him put her in a costume. I don't believe in dressing up dogs.' Peggy comes on set with Miranda, although they are both currently undergoing therapy for her bark problem. 'She's very protective of me.' What is she trying to say? ' "If you come near my owner I will kill you in the face." ' Does Peggy sleep on her bed? 'Not any more.' That proves it - Miranda is ready for love. 'Interesting,' she replies. 'Maybe I am. Finally ready, aged 39 I've got years left before I'm 40, though.'

At this point, Miranda, still horizontal on the hotel bed, starts to peel and eat a banana. 'Sorry if this is a little eccentric. I've been up since 4am.' She has been broadcasting the Radio 2 breakfast show with Jon Holmes. When I chat to her about how it went, two weeks later, she brushes off the negative feedback: 'That was totally out of proportion. Every show gets comments. The feedback on Twitter was really good. Chris [Evans] is obviously the master and we weren't comparing ourselves. But Steve Wright said he thought we had good "atmos", and Lulu came on and taught Jon Holmes how to dance live on air. I really enjoyed doing it, except it was too early. If they could schedule a brunch show for me, I'd do it.'

Disposing of her banana skin, Miranda explains: 'I do generally try to eat healthily. The reason I'm set on losing weight is that I'm not naturally this big, I'm naturally lean. When I put on weight, I feel like this isn't me, this isn't right. I feel like I'm wearing a fat suit. I went with it for a bit, and didn't mind it, but now I'm going to be 40 next year I want to get it off for health's sake, so I can go into a new decade feeling healthy.'

Now she's getting out a little bag of almonds. The last person who did this in an interview with me was Elle Macpherson. Is eating an emotional issue for Miranda? 'No, I've just got such a big appetite. Look, too many almonds! If I was naturally this size, I would just crack on with it and go, "Well, that's just me." If you're naturally a certain size I think it suits you and you can see that. There's no point in trying to conform for the sake of it. People are meant to be different shapes, and their different shapes are so interesting and, ultimately, why people fall in love with them.'

Miranda the sitcom was a surprise hit, comforting as cocoa and proud to be prudish: a scene featuring a penis-shaped chocolate lollipop sparked a high-level meeting, and was reshot with the offending item less visible. 'I had reservations that it would succeed at first,' says Tom Ellis, who plays the heart-throb Gary. 'I always found it funny but I wondered if other people would. It doesn't have a place in the evolution of comedy. After The Thick of It and so forth we assumed the sitcom had died, but audiences do want to laugh.'