Seving delicious Mauritian products on the market Walthamstow. Work only on Saturdays. Mauritian chicken Bryani, soon pouri, roti, Neapolitan, and ice Alouda. The market is Walthamstow in the London borough of Waltham forest, is the longest daily outdoor market in Europe. It takes all but the last 100 metres of Walthamstow high Street.