walk the aisles of Walmart, Piggly Wiggly or Trader Joe’s and you’ll find mochi in all forms: chubby mochi rounds filled with ice cream, mini marshmallow-like rainbow mochi, mochi cake mixes. Mochi is a dense, chewy rice paste first popularized in Japan, and if you haven’t encountered it at the supermarket, you’ve more than likely seen it elsewhere. Mochinut, a mochi doughnut chain with popular pistachio, red velvet and Nutella treats, is expanding across the country, and Mochidoki, a mochi ice cream company, is branching out into grocery stores. Glutinous rice flour gives mochi sweets their pleasing elasticity, a texture that gained traction with the boom of bubble tea and its gummy tapioca pearls known as boba. “That chewy texture is referred to as QQ, which loosely translates to ‘bouncy’…