Step 1

Bring chicken, kombu, ginger, star anise, cinnamon, cloves, stock, and 2 cups water to a simmer in a large pot over medium heat. Reduce heat to maintain a low simmer and cook until chicken is tender. Transfer chicken to a plate.

Step 2

Strain broth through a fine-mesh sieve into a large bowl; discard solids. Return broth to pot and add rice, fish sauce, and palm sugar. Bring to a simmer and cook until rice is very tender, 18–20 minutes. Shred chicken and return to pot; season soup with more fish sauce.

Step 3

Divide soup among bowls; top with scallion, jalapeño, cilantro, and onion.