Rinse the rice under cold water until the water runs mostly clear.
Add the rice, milk, sugar, and salt to a medium heavy-bottomed saucepan.
Place the saucepan over medium heat and bring the mixture to a gentle simmer.
Reduce the heat to low and cook for about 30–35 minutes, stirring frequently to prevent the rice and milk from sticking.
Continue cooking until the rice is tender and the mixture becomes thick and creamy.
Stir in the vanilla extract, cinnamon, nutmeg, and butter.
Add raisins if desired and mix well.
Remove from the heat and allow the pudding to cool slightly.
Spoon the rice pudding into serving bowls.
Sprinkle with cinnamon, chopped almonds, or pistachios before serving.
Serve warm or refrigerate for 1–2 hours and enjoy chilled.