Stand each ear of corn up in a bowl or plate and, holding it sturdy, carefully run a sharp chef's knife down the length of the ear to shave off the kernels.

Combine the kernels and half and half in the jar of a blender. Blend at a high speed for at least 2 minutes, until smooth.

Pass the pulp through a fine mesh strainer to get rid of the coarse parts, using a spoon to press it so you get all the liquid out. Discard the solids.

In a large pot, combine this liquid with the sweet condensed milk, butter and salt. Cook over medium heat, stirring often with a wooden spoon, until the mixture thickens and reduces, about 30 minutes. Make sure your pot is large enough and that you do not leave it unattended and stir often, or it can boil over.

Pour the curau into individual serving cups and dust with cinnamon.

Serve warm or chilled.