Clean the moong dal rubbing with a moist towel.
Boil water and sugar in a pan over medium heat, for about 2 minutes. Remove from heat. Add cardamom powder and saffron set aside.
In a heavy bottom frying pan, roast moong dal over medium-low heat. Keep stir-frying till it's light brown in color and becomes aromatic. Make sure to cook on low heat otherwise dal will not be toasted inside. This will take about 8 minutes. Remove from heat and let it cool to room temperature.
Once dal comes to room temperature, grind it to a powder lightly grainy.
In a heavy bottom frying pan, add oil and roasted moong dal powder, mix it well, and again roast over medium low heat for about 3 minutes. Dal will become dark in brown. Notes: After adding the syrup color will become a little lighter.
Add syrup to the dal, a little at a time. The syrup will splatter as you are adding syrup, keep stirring and mix it well, cook for 2-3 minutes. Halwa should be the texture of soft sticky dough.
Serve the halwa warm.