The Belgian Prime Minister was pelted with fries and mayonnaise, in a precedent-setting attack on Monday by protestors against a new austerity program. Belgian fried potatoes, more widely known as French fries, are a national dish in this country which claims their invention. Fries are most often served with mayonnaise in Belgium and 95% of Belgians patronize a Friekot stand where they are widely sold, at least once a year.