Grind nuts and cardamom to a coarse powder in a mixer grinder. Keep some some for garnish.
Heat the milk on medium heat until it begins to boil. Stir often so milk does not stick or form a thick skin. Add a few strands of saffron to the milk.
After it reaches a boil, lower the heat to medium-low. Keep the milk at a gentle simmer.
Let the milk reduce until it is about one-third of the original volume. This takes about 30 minutes. Stir frequently in the beginning to prevent sticking.
When the milk has reduced and looks thick and creamy, add sugar and condensed milk.
Cook for 5 minutes on low flame. Add the powdered nuts.
Mix well and let it cook for 5 minutes. Switch off and cool down completely.
Pour the kulfi mixture into kulfi molds, small steel molds, popsicle molds, or paper cups.
Tap molds gently on the counter to remove air bubbles.
Cover the molds with lids, or aluminium foil, insert an ice cream stick and freeze for at least 8–10 hours or overnight until fully set.
To unmold, dip the mold in water for a few seconds.
Gently hold the mold and pull the kulfi out. Place it on a serving plate.
Garnish with extra nuts, a few saffron strands, or a light dusting of ground cardamom if desired. Serve immediately.