Parents face some stupendous challenges ushering children through early life, but few are as stressful as shielding them from fast food. It requires rigorous self-discipline and the ability to inflict cruelty, and in my experience most parents only sustain the latter. Avoiding McDonald's, KFC or any of the myriad instant food joints that fuel the western world and drive advertising schedules on children's television is always difficult, but on long journeys it is a test of nerve that pushes principles to the limit.

We have recently moved to Australia, and spend quite a lot of time exploring our corner of that huge country. Highways in Australia are littered with two things: dead kangaroos and fast-food outlets. You can drive for hours on end and see nothing but flyblown carcasses, then all of a sudden come upon a clump of brand names grouped together like pit stops at a grand prix, selling overpriced, unappetizing food that will travel heavily with all who eat it. Either that, or the children throw it up.

We've just been on holiday to a charming backwater called Town of 1770. It is a remote hamlet that bills itself as the 'Birthplace of Queensland', because it was the spot in that state where Captain Cook first stepped ashore in, you guessed it, 1770. It is a beautiful place with a rugged headland, an estuary and some fine beaches. To tell the truth, Cook thought the place a dump, which just goes to show that, although he could sail, he wouldn't know a real-estate opportunity if it got up and bit him: the rich are now building million-dollar homes anywhere they can, while the locals scratch their heads and watch their property values double each week.

One of its charms for me, when we stayed there, was that it was a long way from anywhere, which for us meant a six-hour drive north from Brisbane on the Bruce Highway. It had many advantages, such as no mobile phone coverage, which restricted communication with friends and colleagues back home. There was minimal television on offer, and the road had only just been given a proper surface. You could go out for a meal there, but there was not a McDonald's for 200 miles.

The children weathered this deprivation patiently, but two hours into the drive home from Town of 1770, the first sign offering a fast-food fix triggered a Pavlovian response from the back seat. 'I'm hungry, can we stop for dinner?' begged the nine-year-old. As always in such situations I was torn between the desire to give the kids what they wanted, just to shut them up — er, no, I mean, reward them for being so patient on a long drive — and sticking to my rule about never feeding them junk. I resolutely drove past the beckoning signs, parked in a spot where there was no temptation, and handed round fruit and cereal bars.

It's all very well fobbing your kids off with wholesome snacks, but payoff time comes sooner or later, and this is where I reveal my hot tip: tell them there is a feast of fast food waiting for them at home. The ingredients are waiting in the store cupboard, and within half an hour of arrival, a meal fit for any child is waiting on the table. The saviour in this situation is a spicy Mexican dish called nachos, which you can make in five minutes in a microwave. It is a meal which requires minimum effort, but offers maximum taste and goodness. Kids, love this food, and adults too — and I love giving it to them because it is cheap, easy, quick and leaves fast food standing in the blocks when it comes to nutritional value. All you require is onions, spices, tomatoes and beans which you cook together and serve on crispy corn biscuits. I've never met a child that didn't simply love it.