Wash and pit 250 grams of fresh cherries. Blend them in a mixer to make a smooth puree. Set aside.
In a heavy-bottomed pan, heat 1 liter of full-fat milk on medium flame. Keep stirring occasionally to avoid burning.
Once the milk starts boiling, reduce the flame and let it simmer until it reduces to half its original quantity. This will take approximately 20-25 minutes.
Add 150 grams of sugar to the reduced milk and stir well until the sugar dissolves completely.
Add the cherry puree to the milk mixture and mix well. Cook for another 5 minutes on low flame.
In a small bowl, mix 2 tablespoons of cornstarch with 4 tablespoons of cold milk to make a smooth slurry. Add this slurry to the cherry-milk mixture and cook for another 3-4 minutes, stirring continuously to avoid lumps.
Remove the pan from the heat and let the mixture cool down to room temperature.
Pour the cooled cherry kulfi mixture into kulfi molds or small cups. Cover with aluminum foil and insert ice cream sticks in the center of each mold.
Freeze the cherry kulfi for at least 6-8 hours or overnight until it sets completely.
To serve, gently remove the cherry kulfi from the molds by running them under warm water for a few seconds. Enjoy!