Pour milk in a pan and get it to rolling boil. Add sugar and in simmer continue boiling till it thickens which may take 20 to 30 minutes. Keep stirring every now and then to avoid burning at the bottom.
When milk reduces to half, add the coarse mixture of almond and pistachio. Continue cooking for few more minutes. Switch off the flame and let it cool down to room temperature.
Next puree the mango pulp such that no chunks have retained, add it to cooled milk. Mix well.
Next pour this kulfi mixture to moulds, insert ice cream stick and freeze for about 6 to 8 hours. Take out from freezer and hold the backside of mould under running water for a while.
Keep it aside for a minute and then carefully de-mould kulfi from moulds. Beautifully orange colored mango kulfi is ready to serve.