You can make this simple porridge using any sort of sweet meat squash or pumpkin.
¼ cup kidney beans
1 ½ lb pumpkin or squash (danhobak 단호박) -- you can use Kabocha squash, butternut squash or any species that has sweet meat
1 tsp sugar
1-2 tsp salt
1 cup sweet rice flour
7-8 tbsp boiled water
5 tbsp sweet rice flour
½ cup of water
Soak the kidney beans in enough water to cover the beans for at least 1 hour.
Peel the skin of the squash and cut into smaller pieces. Add the slices in about 5 cups of water and boil until the squash pieces are tender. Cool, then blend till smooth in a blender.
Peel the chestnuts and cut into halves. Put the soaked beans and chestnut pieces into a pot. Add 1 tsp of salt and cook until the beans get tender enough, but not soft. Remove from heat and drain.
Form the small rice balls: put a cup of water to boil. Mix 1 cup of sweet rice flour, ½ tsp of salt and 1 tsp of sugar. Slowly add boiled water to the mix to make a firm paste -- add 1 tbsp of water at a time, up to 7-8 tbsp of boiled water. Once the batter is firm, roll into small balls using your hands -- we call them "birds eggs" (sae al) in Korean, about 1" in diameter.
Separately, make some thickener for the soup: add 5 tbsp of sweet rice flour into ½ cup of water – stir well.
Add the blended squash mixture into large pot, add the rice flour thickener and the rice balls. Stir and bring to a boil. Let it simmer for 4 minutes, then add the cooked beans and chestnuts and let it simmer for a few more minutes. Add sugar and salt to taste. Best served warm.