Place milk in a large pot and bring to a boil. Reduce the heat to medium low and simmer gently for about 45 minutes. Occasionally, whisk milk and bottom of pot to ensure that the milk solids do not catch and burn on the bottom. Reduce the milk by two-thirds until you have 1 litre. The reduced milk will be a light brown colour and have some small chunks of milk solids. Pour the reduced milk into another container to let cool to room temperature.

Place the reduced milk, maple syrup and , chopped walnuts and ground cardamom in a blender and puree well.

Pour the mixture to almost the top of each popsicle mould. Cover the top of the mould tightly with a piece of aluminum foil. Carefully press on the top of the aluminum foil to carefully see the outline of each popsicle filling. Using a paring knife pierce the aluminum foil in the center of each mould. Insert a popsicle stick fully into each opening (see photo below). Place in a freezer and freeze for a minimum of 4 hours or preferably overnight. (Most recipes suggest placing the popsicle sticks in when it is semi-frozen. Doing it the way I suggested means you can simply walk away and not worry about when is it semi frozen).

To unmold the kulfi, quickly run the sides of the moulds under warm water and carefully put out the frozen kulfi.