Superior home cooking at the Three Horseshoes at Madingley
Restaurants open in London at the rate of two or three a week. So what incentive is there for the reviewer to turn their back on this steady supply of hot meals? There's the inconvenient knowledge that most newspaper readers don't live in London and that restaurants occasionally open elsewhere. At the risk of giving away the tricks of the trade, this means having to buy an Away Day ticket and setting off with a fellow metropolitan to carry out a forensic examination of lunch in the country. Or, given that it's harder than you might think to find a gastronome to give up the best part of a November Wednesday, we may end up going alone with only a copy of Brillat-Savarin for company.

A more natural, if less systematic, approach is to combine it with the overdue visit to the out-of-town chapter of the family. This releases them and us from their Hostess trolley and gives us a team of tasters, albeit not necessarily biddable ones, to put the place through its paces. The drawback of this more accurate and sobering test of the cost of eating out en famille, is that they will be strangers to the rules of reviewing - that everyone should eat something different, and that each must provide a pithy summary of their opinions. They will all order steak and then, pressed for a soundbite will pronounce it, "very tasty", but what else are restaurants for if not going out for fun with your family? That's assuming there's a suitable one. Cambridge, home of the common-law-in- laws, seems to have nothing in the way of restaurants. The candlelit place that's open evenings only was a fat lot of use for Sunday lunch.

The Three Horseshoes at Madingley, a village where even the scout hut is thatched, included in the latest edition of the Good Food Guide for the first time, although it has had the same chef for four years, was all we could find within a 10-mile radius. No wonder, then, that Sunday lunch was fully booked by Friday. The bar, painted pink and hung with prints (it's not really a pub for locals), doesn't take reservations, although the same menu is served there and in the conservatory restaurant where the cavalry twill set and a disproportionate number of Americans had had the foresight to book. We had to do the towels-on-the-beach equivalent of parking the baby's changing bag on a table for six just after midday and fending off invaders for 20 minutes.

"Very informal service", is how the menu describes Sunday brunch and lunch in the bar, meaning you have to get your own drinks, while sixth formers in white shirts and bow ties ferried the food, and the pots of tea our party chose as an aperitif. Though the youth who turned up at the table holding two plates and saying "halibut?" could have been instigating a parlour game for wet Sunday afternoons, he coped well with such a full house. Demographically, we represented a fairly typical target market. Eleven-year-old twins with half-term appetites, their baby boom generation parents, me and my consort who stop thinking about food only when we're eating, and our baby who brought his own lunch but was still determined to eat the menu card. Apart from an illustration of autumnal produce, this listed dishes that would have been more at home in anything-goes- Notting Hill Gate than 60 miles into the East Anglian countryside, I had to arm-twist the adults into having starters from a menu lightly peppered with words like wasabi and pancetta. Piedmontese cabbage soup with fontina slipped down nicely and uncontroversially. The crostini could have come from a smart wedding reception. "Is that all?" said my military brother- in-law looking at his ration.

I didn't have the heart to insist someone try loin of pork braised in milk and lemon with herb polenta, or roast chicken with ginger and lemon grass risotto, which suggested the kitchen was trying to prove it wasn't in a culinary backwater. Anyway, our officer in charge led his company in a concerted advance on roast lamb. Perfectly combining familiarity and sophistication, it came in thick, well-cooked slices studded with pearls of garlic and scattered with rosemary, the fat golden and crisp. Dauphinoise potatoes and beautifully crunchy green beans with the irrelevant addition of diced red onion completed the picture of a posh roast very well.

The London contingent's more adventurous ordering was a tactical error. Halibut with parsley crust was dry, and I'd rather draw a veil over black bean chilli, except to say the menu should have mentioned that this was a vegetarian dish consisting almost entirely of black beans stained even blacker with an excess of soy sauce. The others looked at me as if to say: "Well, what did you expect?"

Children full of lamb and chips refused to be tempted by honey or burnt sugar or rum and raisin ice cream. But deliciously grown-up panettone bread-and-butter pudding, and deep-filled lemon tart with caramelised top, lime and vanilla marmalade and creme fraiche made amends for the fish and the beans. Even so, our happy family's verdict was that, yes, the lamb was very tasty, and it's just as well there were chips as a side order. "But it's a pity they don't have any plain vanilla ice cream." And mine? I'd rather the in-laws came to London next time we eat out. Lunch was pounds 120 for six.

The Three Horseshoes, Madingley, Cambs (01954 210221) Lunch Mon-Sat noon-2pm, Sun 11.30am- 2.30pm; dinner Mon-Thur 6.30-9.30pm, Fri, Sat 6.30-10.30pm. Sun 7-9.30pm. Average pounds 20. All major credit cards