Instructions. Using the back of a knife, lightly smash the lemongrass on a cutting board. Cut the lemongrass into 1-inch pieces, and add to a large stockpot. Add lemongrass, ginger, fresh lime juice (or kaffir lime leaves), chicken broth, and the white parts of the green onions to the stockpot, and stir to combine. Bring to a boil over high heat.Web