Rinse 1 cup moong dal and soak it in water for 4 to 6 hours
Drain the water and grind the soaked dal to a coarse paste with little or no water
Heat 1/2 cup ghee in a heavy pan
Add the moong dal paste and cook on low heat
Stir continuously until the dal turns golden and aromatic
Add 1 to 1 1/2 cups sugar
Add 1/2 cup water if needed to help dissolve the sugar
Cook while stirring until the mixture thickens
Add 1/2 teaspoon cardamom powder
Add chopped nuts like almonds, cashews, and pistachios
Add saffron soaked in warm milk if desired
Cook until the halwa leaves the sides of the pan
Serve hot
Garnish with more nuts if desired