I never heard of Hainan Chicken growing up, not surprising since I grew up in New England, but my parents never mentioned it. However, one of my favorite dishes that my mom would make was congyouji, or scallion-oil chicken. I find it very similar to Hainan Chicken, though rice is not a required component of congyouji. Can @jlee or any other Chinese chefs/food scholars shed some light on any connection between these two dishes?
(Image of Johnny’s Nainan Chicken from the article.)