What do you get when a continent-hopping, tech-loving food geek opens a grocery? Marx Foods, Justin Marx’s specialty-foods shop in lower Queen Anne. After 16 years of sourcing rare ingredients for chefs of top restaurants, Marx is bringing his adventurous palate and taste for trends to Seattle’s home cooks. Inside the small store, exotic ingredients like hibiscus vinegar, dill pollen, and maple cream sit neatly on cherry shelves, across from a glass case filled with larded Mangalitsa bacon and other boutique meats. Not sure what to do with that kangaroo steak? QR codes throughout the store connect shoppers to Marx’s vast online resources, including video introductions to unusual ingredients like geoduck clams and fregola sarda (an Italian couscous), and recipes for how to use them at home.