To begin, place water, a pinch of salt, lemon zest strips, and cinnamon stick in a medium saucepan. Bring to a gentle boil over medium heat. Transition to adding rice.
Add the rice to the boiling liquid and cook for 8–10 minutes, stirring occasionally, until it begins to soften but is not fully cooked. Move on to infusing with milk.
Reduce the heat to low and slowly pour in the milk, stirring constantly to prevent the rice from sticking. Continue cooking gently so the grains absorb the milk evenly.
Allow the rice to simmer for 25–30 minutes, stirring regularly until the mixture is thick, creamy, and the grains are tender. Transition to sweetening.
Stir in the sugar, ensuring it dissolves completely. Cook for another 5 minutes to blend the sweetness fully. Prepare to temper the egg yolks next.
In a small bowl, whisk the egg yolks. Add a ladleful of hot rice mixture to the yolks while whisking to prevent curdling. Gradually stir the tempered yolks back into the pan.
Cook over very low heat for 2–3 minutes until the pudding thickens further. Do not allow it to boil, as this will scramble the eggs. Remove the lemon zest and cinnamon stick.
Spoon the Arroz Doce into a shallow serving dish or individual bowls. Allow to cool slightly before garnishing.
Dust with ground cinnamon, creating the traditional lattice pattern using a paper stencil or steady hand. Serve warm or at room temperature for the best flavour.