How do restaurants process your orders?

Behind the scenes in the kitchens of Le Gavroche and Nobu

A recent dinner at Zuma, the new, chic Japanese restaurant in Knightsbridge, highlighted one of the most common frustrations for anyone who makes their living recommending restaurants.

Our party of four arrived at 8.15pm, went straight to the table and had a good meal although the service turned ragged towards the end. Four friends arrived half an hour later, had a drink at the bar before sitting down three tables away from us and had a far less enjoyable experience. What explains this inconsistency?

From personal experience as a restaurateur I know that there is not one single factor. Pressure in the shape of too many simultaneous bookings is an obvious cause, one reason why experienced receptionists try to spread lunchtime reservations from 12.45 to 13.15, although everyone tries to book for, and arrive, at 13.00.

Then there is the human element. Confusion between a head or sous chef calling the orders, and a chef de partie, cooking a particular section of either meat or fish, who fails to hear one table's order means that the customer may have to wait unduly – especially if the order includes a well done meat dish. And then there is the processing of the order itself.

Flimsy bits of paper used to be the norm. These would make their way, somewhat riskily as they could easily get lost, either in the hands of poorly paid commis waiters or in electric lifts, from the diningroom to the kitchen. Today, thanks to technology, the orders pass via electronic screens in the restaurant to a series of printers around the kitchen. It is this kind of system which has allowed restaurants to spread in physical size and enabled chefs to broaden the menus they can offer. To contrast these very different types of control systems I spent two lunchtimes in the shadow of Michel Roux Jr at the still traditionally run Le Gavroche and Mark Edwards at Nobu which, he openly admits, could not survive without its electronic lifeline.

Not just a commitment to quality unites these two kitchens, however. Walking around each in the quiet lull before lunch, I was struck by the United Nations-like make-up of their brigades. Edwards leads a team of chefs from Somalia, Sri Lanka, Thailand, Malaysia, Australia, France and, of course, Japan whereas Roux's line up includes Portuguese, Swiss, New Zealanders, Italians, Japanese and of course French as well as a female American chef referred to thoroughout service as 'Miss Texas'. Both also find distinctive uses for their recycled three litre tubs of Karla clarified butter. Roux keeps his full of a julienne of leeks and carrots, tomato concassé and their own mayonnaise in the fridge next to 90kg of conserved truffles whilst those in Nobu stand on a ledge by the sushi counter full of sliced ginger and wasabi.

But what is also crucial to both restaurants' survival at lunchtime is speed and efficiency of service. Both need to attract an impatient business clientèle and both chefs compose their very diffferent menus accordingly. Roux has a three-course lunch menu with three choices at each which with wine is £40 per person – but the kitchen has to be ready to cook the entire à la carte menu too which at least two or three tables will order. And whilst Nobu's kitchen is continually geared to serving a vast permutation of tempura, cooked dishes, sushi and sashimi, it also serves noodle and donburi dishes as well as bento boxes, known in the kitchen as 'in and out' boxes because that is how quickly many want to eat lunch.

Edwards and Roux themselves both regularly do the 'pass', or the calling and expediting of orders, with Roux alternating weekly with his sous chef. Edwards mainly cooks at lunch but a disagreement with a motor boat propellor had left him with eight stitches in one hand and calling rather than cooking for several days.

In the highly structured French system everything revolves around Roux who barely moves during service, calling orders, collating dishes, tasting sauces and napping them over the main courses, and wiping the rims of the plates before they are whisked away. Edwards, by contrast, is in perpetual motion but even his high energy levels, hindered by his kitchen's awkward shape, cannot take him to all the sections supplying food to the waiting staff.

Roux's lunch service begins with a false dawn. His customers are initially seated either in the bar or lounge where they are served canapés which are called for by a waiter who writes their pre-assigned table number on a small blackboard. This gives Roux a picture of how many are in the restaurant and he is not looking happy. 'We've sent out 30 canapés already but there's not a single order taken. We're going to get hammered.'

His pessimism is ill founded. At 12.45 the first paper order arrives with the waiter handing one copy across the heated counter to Roux and clipping another to the right hand of a rail on his side which in half an hour will resemble a washing line in the wind (there are two other copies of each food order, one for the waiters' station in the restaurant, the other for the cashier). Roux, his back to the kitchen, turns and calls the table's starters and main courses and the various sections of his kitchen respond with a wave of 'Oui, chef's.

As the orders come in, the pieces of paper move gradually to the left and the pace, volume and action mount. Amuse-bouches, small pieces of marinated salmon, are whisked away and then the first courses, half a cold lobster (very popular with Roux shouting 'This is Lobster City' as the orders come in), an oxtail jelly and a three small brochettes of grilled swordfish. The first two come from the larder section, the latter from the fish section, a tactic thoughtful chefs employ to ensure that one section of the kitchen is not submerged with too many orders which slows the whole service down.

It is at this next stage when diners are eating their first course that this particular system is at its weakest. The fish and meat chefs have begun to cook the orders when they are first called but will not begin to finish them until Roux calls again that they can be sent. With no view of the diningroom, Roux depends entirely on his waiting staff who patrol the room, with the most experienced only too aware of the precise timing required to avoid any delays. They tell Roux when this is happening and he continually chases them asking 'Is table 17 clear?' At this stage, to preclude future recriminations, the order which has been struck through by the waiter when the first courses were served, is folded in half so that both he and Roux know that their main courses can be sent.

Nobu has no such central order processing. Whilst the waiters do take the orders on paper this is merely a single sheet which they then take to the closest Micros screen before tapping in the table's whole order. Technology then intervenes, breaking down the order into the four main constituent parts of the menu and sending each accumulated order to each distinct cooking section. Within seconds printers are then communicating these orders to the sushi chefs, the salad section, the hot section which is in turn split into two, chefs preparing tempura and those seemingly incessantly cooking Nobu's famous black cod with miso, and the dessert section.

At either end of the narrow, incredibly busy corridor which faces on to the main cooking area there are two oases of relative quiet. At the far end the two pastry chefs are making caramel, piping Happy Birthday around the edges of two plates and getting their section ready for their orders which the printer will start churning out around 13.30.

At the beginning of the corridor the printer by the sushi section is spewing out orders which are calmly picked up by No 1 sushi chef and laid out on the glass counter behind which and he and his four colleagues work. Here there is no shouting of orders, the loudest noise is the printer, and the sushi chefs follow an unerring rhythm: read, choose, slice, plate, wipe down. When each order is finished it is placed back on the ledge with the print-out on top of it; a waiter checks them, spikes the order and whisks it off to the table.

Edwards spends 90 minutes hotfooting it across four metres of counter separated most inconveniently by a structural wall. Directly in front of him are four chefs to whom he calls each order as it emerges from the printer before handing it over for them to attach to a rail similar to the one at Le Gavroche and most restaurants in the world.

What distinguishes his role is that as so many orders from its huge menu are composite (there are close on 200 different items and on a busy night the kitchen can send out 5000 different plates) Edwards needs to call to, monitor and cajole the main hot kitchen, the salad section which also supplies the miso soup, the tempura chefs and occasionally the sushi section for the bento boxes and 'omakase', the tasting menu. In between he wipes down the bento boxes and the rim of every dinner plate and scoops the rice out of the steamer before checking each order and calling for a waiter. Sustained by water and a good sense of humour – the chefs collapse with laughter when an order comes in for a vegetarian mushroom salad – they have served 150 customers in two hours when a waiter walks in to say that the last customer has been served.