Boil 1 liter full-fat milk in a heavy-bottomed pan
Simmer on low heat, stirring often, until reduced to about half
Add 1/2 cup sugar and stir until dissolved
Add 1/2 teaspoon cardamom powder
Add 2 tablespoons chopped nuts, such as almonds and pistachios
Add 1 tablespoon milk powder if desired for a richer texture
Remove from heat and let the mixture cool completely
Pour into kulfi molds or small cups
Insert sticks if using molds
Freeze for 6 to 8 hours or until set
Unmold and serve chilled