In large saucepan, bring the chicken broth & rice to a boil over high heat, cover and reduce heat so the broth is just simmering. Cook for 20 mins or until rice is very tender. In a small bowl, whisk lemon juice into egg yolks. Turn heat down on rice and with a big spoon or ladle, slowly add about 1 C of the rice-broth mixture to the lemon-egg mixture, whisking constantly. Return the lemon-egg-broth mixture to the remaining rice and broth in the saucepan, whisking to combine. Cook over low heat until the soup is slightly thickened and creamy. Taste and add salt & pepper if desired. Adjust the tartness with a little extra broth or lemon juice, respectively.