Cook 3 cups of cubed sweet potato in 11/4 cup of water.
Melt 2/3 cup of grated jaggery adding little water & strain to remove any impurities. Add the jaggery syrup to the cooked sweet potato & mix well for 5 minutes.
Add 11/2 cups of randaampaal to the sweet potato-jaggery mixture & cook on medium low heat for 10 -15 minutes. Finally add 1/2 tsp of powdered cardamom & remove from heat.