Combine rice, milk, sugar, cinnamon, and salt in a medium saucepan over medium.

Simmer gently, stirring frequently to prevent sticking; reduce heat to low.

Cook 20-25 minutes, stirring occasionally, until thick and creamy, rice is soft, and pudding coats a spoon back.

Off heat, stir in butter and vanilla until butter completely melts.

Rest 5 minutes to thicken slightly; it continues thickening as it cools.

Serve warm topped with berries, raisins, honey, or almonds and extra cinnamon if desired.