Preheat your oven to 325°F (160°C). Butter a 9×9-inch baking dish thoroughly, including the sides.

Rinse 1 cup (200g) of short-grain rice under cold water until clear.

In a medium saucepan, combine rinsed rice, 2 cups (480ml) whole milk, and a pinch of salt. Bring to a gentle simmer over medium-low heat, stirring occasionally. Cook until rice is tender but still slightly firm, about 18-20 minutes.

While the rice cooks, whisk together 3 large eggs, 1 can (395g) condensed milk, 1 teaspoon vanilla extract, and 1 teaspoon ground cinnamon in a large bowl until smooth and slightly frothy.

Carefully stir the warm cooked rice into the egg and condensed milk mixture gently to avoid scrambling the eggs.

Pour the pudding mixture into the prepared baking dish. Dot the top with about 1 tablespoon of butter.

Bake in the preheated oven for 50 to 60 minutes until the top is golden and slightly puffed. The edges should be set and the center should jiggle slightly.

Let the pudding cool for at least 15 minutes before serving. Serve warm or at room temperature, optionally sprinkled with cinnamon or toasted nuts.