The cannon will fire not once, but three times tonight in Fez as the tiny sliver of moon is sighted to herald the start of Ramadan on Wednesday. As the boom echoes from the ancient labyrinthine city across to the 'nouvelle ville', the students in my class will erupt with excitement and I know I won't be able to teach them much more. So what should I say, I asked, to my Muslim friends about to start their month of fasting? "Ramadan m'barak"; "A blessed Ramadan"... these are the words on everyone's lips tonight.

It's been an interesting week of watching how the city and the people of Fez prepare for what will be a daunting but achievable task. At least the temperatures have dropped from the late 30s to a very cool morning and evening, and carrying a bottle of mineral water is not quite so essential.

Throughout the medina, café tables are piled so high with deep-fried sweet pretzels, samoosas and sausage-shaped rolls filled with almond-dotted sesame paste dripping with honey, that I wonder if everything will sell. I'm assured it will; there are large plastic buckets hanging above the displays which you can buy to take home your purchases. And when you've spent a day wishing you could eat something, a sugar rush from these sweetmeats is probably not what your body needs, but certainly what it craves.

I've been watching the b'stilla pastry cooks. Fez may be the spiritual capital of Morocco, but it's also the home of b'stilla, an extremely thin pastry that makes strudel or phyllo pastry look positively leaden. There's a large plastic bowl of mixture, and men are making the pastry. They take a fistful and roll it onto a griddle with the heel of the hand, as thin as can be. It takes but seconds to cook, and is then whipped off, added to the pile of sheets, and oiled with a pastry brush.

Housewives cram around the pastry cooks and haggle for sheets of the wafer-thin delicacy. They fashion sweetmeats from it, or make the famous b'stilla pies that contain pigeon meat and almonds and are dusted with icing sugar and cinnamon. It's the taste of Fez — sweet yet savoury — and definitely worth trying. B'stilla is always available; it's just that at this time of year it's doubly valued.

Alcohol is forbidden during Ramadan; bottle stores close a few days beforehand, and stay closed for a few days after Eid. If you're a foreigner and really desperate, you can show your passport to a retailer, or go to an upmarket hotel to drink at the bar. Of course, alcohol is forbidden anyway for Muslims, but somehow Morocco has a thriving wine industry and it’s common for people to drink alcohol — except during Ramadaan.

Breaking the fast
The fast is broken each evening in homes and cafés across the country as soon as the sun sets. I join friends in a café and we listen to prayers set to music coming from the TV. Then the sound is turned down while we hear the call to prayer emanating from the mosque opposite.

The minutes tick by agonisingly. When the call is complete, the proprietor calls 'b'smillah' and turns up the TV anew, and everyone tucks in. The iftar, or f'touh food differs little from place to place. There's always harira soup, a delicious concoction of vegetable or lamb stock with tomato paste, chick peas, small pasta, lentils, rice, red pepper, fresh coriander and perhaps some lamb or chicken. It's served with dates and some honey-drenched pastries, delicious pancake-type breads, some stuffed with egg and onion, bread, fruit or vegetable juice, hardboiled eggs with salt and cumin and afterwards, mint tea. All for around R10 each.

So here are all the trappings, the sweet things, the harira and the b'stilla pastry, but what's it all about?

Showing commitment to Allah
The four weeks of Ramadan are observed by fasting during daylight hours and eschewing sexual intercourse and smoking. Exempt are pregnant or breastfeeding women, small children, those travelling and the sick and elderly.

The aim is to remind Muslims of their commitment to God and as a spiritual purification. I don't hear any moans, and people seem pleased to take part and of course have great support from the entire community. It’s also the time to wear traditional clothes; the djellabas are beautifully embroidered and the pointy-toed babouches new and shiny.

My students assure me that I'll be woken each morning by the sounding of the cannon. Interestingly enough, I've learned to sleep through the 4am call to prayer, and no doubt this cannon will eventually become routine. But my students wake at around 4am and have breakfast — a big breakfast of fruit, milk, eggs, bread, yoghurt, pancakes, cornbread... then they go back to sleep. This means that 9am classes are now scheduled for 9.30am. Non-Muslims don't have to fast, of course, but we wouldn't think of eating or drinking in front of our Muslim colleagues or students and many of my colleagues do fast.

Later in the evening, between 10pm and midnight, supper is served. Here's the meal that the women have spent their day preparing — in between watching Egyptian soaps I'm told, as there's nothing much else to do — from b'stilla to couscous to tagines resplendent with the wide range of fresh vegetables available in the markets.