¿Como se dice "one-stop shop" en Español? The answer, at least for Latinos who reside in the northwestern reaches of Seattle, is Plaza Latina. Surrounded by car dealerships in a Shoreline strip mall on Aurora, Plaza Latina is a combination restaurant, grocery store, and peluqueria (hair salon, to gringos). The restaurant features a menu del día with traditional Mexican soups and meat entrées, and the place is packed on weekend afternoons with immigrants pining for a taste of home. The grocery store stocks all the staples, including some difficult-to-find exotics, and a very affordable selection of Mexican beers including the rare ballena, or whale-sized, bottle of Pacifico. There's no meat counter, but the in-store bakery turns out an impressive array of pastel-colored treats. Also available: jewelry, CDs, and roughly 5,000 different types of prepaid phone cards. KEEGAN HAMILTON 17034 Aurora Ave. N., Suite D, 533-9440, website TK?