Yum Yum Donuts on El Cajon Boulevard in La Mesa represents the largest privately owned donut chain in the United States, founded in 1971 by Philip Holland in a converted Orange Julius stand in Highland Park, Los Angeles. The El Cajon Boulevard location bakes from ingredient blends produced by the company's in-house manufacturing arm, Quality Naturally Foods, a vertical integration model that supplies dough mixes and glazes across the chain's 94 California-only stores and contrasts with the single-origin roasting focus at nearby morning stops like Brew Coffee Spot. Holland refined his technique while working alongside Vernon Rudolph, the founder of Krispy Kreme, in North Carolina before heading west to build the Yum Yum concept around made-fresh doughnuts served from high-traffic storefronts. The menu runs deep beyond ring doughnuts into crullers, bear claws, apple fritters, and breakfast sandwiches, a quick-serve breadth comparable to the sandwich-heavy counter at Trolley StopDeli on the La Mesa grab-and-go circuit. In 2004, the chain acquired Winchell's Donuts and its roughly 200 locations, consolidating both brands under a single manufacturing and distribution infrastructure headquartered in the City of Industry.