In a heavy-bottomed saucepan, bring the milk to a boil over medium heat.

Reduce the heat to low and let the milk simmer until it reduces to half its original volume, stirring constantly to prevent sticking and burning.

This will take approximately 45-60 minutes.

Add the cooked rice and raisins to the simmering milk, stirring continuously.

Stir in the sugar and mix well until it dissolves completely.

Continue to cook the mixture over low heat, stirring constantly, until it attains a thick, sticky consistency.

This will take about 15-20 minutes.

Once the rice pudding reaches the desired consistency, remove it from the heat and let it cool slightly.

Serve the rice pudding warm or chilled, as desired.