(NEWSER) – You might want to pack a lunch today. This summer's series of fast-food walkouts continues in a big way, as workers in at least 58 cities across the country go on strike. Organizers are calling it the largest such strike to date. The workers plan to picket the likes of McDonald's, Burger King, and KFC during lunchtime as they call for wages of $15 an hour and the right to form a union without fear of retaliation, the AP reports. The previous "biggest strike" occurred in July, when as many as 2,220 workers participated in a seven-city strike.