Rinse and drain the rice. Add the rice, Abuelita chocolate tablets, and cinnamon to a large bowl. Pour in 2 cups of hot water and stir. Cover and let soak for at least 4 hours, or overnight, until the rice has softened and the chocolate has dissolved.

Transfer the soaked rice mixture to a blender. Add the sweetened condensed milk, vanilla extract, and 2 cups of whole milk. Blend until the rice is finely broken down and the mixture is smooth and creamy.

Pour the mixture through a fine-mesh strainer or cheesecloth into a large pitcher, pressing or stirring the solids to extract as much liquid as possible.

Stir in the remaining 1 cup of milk and 2 cups of water. Taste and adjust the consistency with additional milk or water if desired.

Pour over a glass filled with ice. Serve chilled and enjoy!