Add water as needed and cook the split Bengal gram well so they can be mashed. NOTE: don't add too much water. Now grind this in mixer for one spin and keep it aside.
Dry roast the fresh shredded coconut until they release the aroma and keep it aside. Now in the same pan roast the Bengal gram paste for few seconds and keep it aside..
In a pan add Jaggery, little water and cook once the Jaggery dissolved well. Add the roasted coconut, Bengal gram paste and mix well. Sprinkle the cardamom power. Stir and cook until they become thick. NOTE: most of the moisture should be gone so we can fill this Kozhukattai.
In a pan heat water as needed to make dough, add rock salt and bring to boil. Remove this from heat. Now add rice flour, sesame oil and make dough. NOTE: remove the dough and knead well.
Make balls out the soft dough size of small lemon.
In a banana leaf coat with oil. now place ball and fatten it. now place the Jaggery mixture as need. Fold round sheet so you cover the Jaggery. NOTE: make shapes you prefer.
Now steam this in idli cooker until they are cooked and serve.