01 - Combine chicken, water, ginger, scallion whites, and salt in a large stockpot. Bring to a boil over medium heat, skimming off any foam that rises to the surface. Reduce heat to a simmer, cover, and cook for 40 minutes or until chicken is tender.
02 - Carefully remove the chicken from the pot and set aside to cool slightly. Strain the broth through a fine-mesh strainer if desired, discarding the cooked ginger and scallion solids.
03 - Return the strained broth to the pot and bring to a simmer. Add the rinsed jasmine rice and glutinous rice. Cook over medium-low heat, stirring occasionally to prevent sticking, for 30-40 minutes until rice has broken down completely and the porridge reaches a creamy consistency.
04 - While the rice simmers, shred the cooled chicken meat from the bones, discarding skin and bones. Keep the shredded meat aside for serving.
05 - Once the porridge has reached your desired consistency, stir in the additional fish sauce and ground white pepper. Adjust seasoning according to taste preference.
06 - Ladle the hot porridge into serving bowls. Top each portion with generous amounts of shredded chicken. Garnish with scallion greens, fresh cilantro, fried shallots, and lime wedges. Add chili oil or sliced chilies if desired for heat.