Grease a flat bottomed pan like a cake tin and set aside.
Powder the cardamom and set aside.
Mix the jaggery in 1 C water. Stir until dissolved completely. Take the arrow root powder in a large mixing bowl. Add the remaining 1 C water and mix until dissolved. Strain the jaggery water into the arrow root water. Add salt and mix well.
Transfer the mix into a sauce pan and heat over medium heat stirring continuously. In about 5 minutes the mix will thicken and turn into a jelly. Add the grated coconut and powdered cardamom. Continue stirring. Reduce the heat if the halva begin to burn on the sides. In a few minutes the whole mix comes together into a single mass that begins to pull away from the sides.
The halva made at this point will be jiggly. For a firmer version cook over low heat for a few more minutes.
Transfer the contents to the prepared pan. Level with the back of the ladle. Decorate with sliced bananas or fried cashew nuts.
Let cool. Slice after cooling.
Do not leave out the salt.
The softer version of this halva will be like thick pudding. It can not be cut into pieces.
Jaggery can be found in Indain grocery stores. You can substitute with sugar and molasses or even the Mexican Piloncillo or similar.
For detailed instructions go to https://oventales.com/koova-kurukkiyathu-arrowroot-halva/ .