When the rice is fully soaked, finely grind the rice with 1 C (out of 5) of water. Depending on the power of your blender, it may not come out fully smooth right away. Try straining it to see if there are any bigger bits. You can grind the bigger pieces a second time with some additional water if you want your jook to be totally smooth. Some people prefer to have their jook with bits that they can chew on. However you like it. Set aside.
Finely blend the black sesame seeds with 2 C of water.Instead of adding all of the water at once, start blending with less water (more like 1/2 to 1 C) and gradually add more.
Mix the blended rice and black sesame seeds in a pot. (NOTE: because I blended my rice and sesame mixture really finely, I just cooked everything together directly in the pot. If your blended mixture is coarse, you may want to separate the solid rice and sesame bits and their liquid by straining. Mix and cook the two liquids first (just for 2 min) and then add the solid rice and sesame bits later).
Turn on the heat to medium high and keep stirring until it starts to boil. Stir in remaining 2~3 C of water as it cooks. Cook at low heat for 10-15 min. Make sure you continue to stir (I used a whisk) to prevent any rice from sticking to the bottom of the pot.
Consistency will be similar to pudding. If you like yours to be a little more thin, add more water (up to 1 C - totaling 6 cups) and it will come out looking more smooth like the first photo on top.
Season with salt (1 tsp) to taste. Do NOT add salt early on while it’s cooking but only AFTER it’s fully cooked. Salt can dissolve the rice and make the porridge watery.
Optionally you can add sugar or honey or serve it on the side. Garnish with some sliced almonds or pine nuts and of course, sesame seeds!