Wash kabocha, wipe dry, and cook in microwave for about 5-10 minutes until exterior softened. When cooled, cut it in half and remove seeds and strings with a spoon. Using a pairing knife, peel the skin. Cube the squash and place in a large pot. Mash it with a spoon or masher (See note).
Add 4 cups of water and bring pot to a boil. Lower heat and continue to stir and mash chunks of squash until smooth, about 25-30 minutes.
In a small bowl, stir together ⅓ cup sweet rice flour with 1 cup of water. Pour mixture into the pot, quickly stirring to prevent lumps from forming. The porridge will start to thicken very quickly.
Bring the contents of the pot to a boil, reduce heat, and simmer, stirring occasionally (make sure to scrape the bottom), about 10 minutes. Adjust consistency to your liking by adding more water if too thick.
While the porridge is simmering, prepare the rice cake balls. Mix all the ingredients and knead until nice and stretchy. Shape into ½ in balls. *
Add honey and salt to pot and stir in. Add rice cake balls and cook for about 5 minutes, stirring often to prevent them from sticking to the bottom. When cooked, the balls will float to the top.
Turn off heat and season with more salt and honey if desired.