So it is the River Cafe, with its Italian-inspired cuisine, which sums up everything he likes in a restaurant. "It's totally unpretentious and the food is just stunning," he says. "They use the finest and often the most expensive basic ingredients. I hate starched table covers, formal service and rich French food," adds the 53-year-old who founded Iceland, now more than 700-outlets strong, in 1970. Walker first visited Rose Gray and Ruth Rogers' fashionable Thames-side restaurant two years ago and eats there on regular trips to London from his Deeside head office.
Its simple mozzarella and tomato salad is the epitome of why, for him, its food is divine. "It's a little thing, but mozzarella can sometimes taste like rubber," he says. "If you have it at the River Cafe the mozzarella is like nothing you've ever tasted. It sparkles like sherbet on your tongue.
"They use top-quality ingredients and are not afraid to say that, in some cases, tinned tomatoes are better than fresh ones - much better than tasteless Dutch ones, anyway. Not being pretentious about food is very important to me."
In any case, the man who guarantees Iceland-brand products contain no genetically modified ingredients says he has no worries on that score when visiting the River Cafe. "GM soya is used only in processed food and everything the River Cafe makes is freshly prepared," he says.
"And at the River Cafe," he adds, "I don't have to wear a tie."
The River Cafe, Thames Wharf, Rainville Road, London W6 (Telephone 0171-381 8824)