In 1967, Idaho potato magnate J.R. Simplot shook hands with McDonald’s CEO Ray Kroc, sealing a deal that made Simplot the first frozen french-fry supplier to the fast-food chain. That deal brought billions of dollars to the Idaho economy. Until then, McDonald’s had purchased only fresh potatoes. The J.R. Simplot Co. had supplied about 20 percent of the spuds that became McDonald’s fries, according to “Behind the Arches,” a 1995 book chronicling McDonald’s rise. By convincing Kroc that frozen fries would deliver consistency and overcome a shortage of Russet Burbank potatoes in the summer — and that he could deliver — Simplot instantly became McDonald’s largest spud supplier. McDonald’s bought potatoes from other sellers as it expanded around the globe, but Simplot remains McDonald’s largest domestic potato supplier, said Dell Thornley, the chain’s director of global supply chain and sustainability. A McDonald’s marketing video released recently offers a glimpse into the Boise company’s role without mentioning Simplot. More