Cut the kernels from the ears of corn and measure them out. As well as the main kernels, you can scrape the husk with the back of a knife to get all the last little bits out (this part often has more of the starch that helps it thicken).

Place the corn in a blender with the milk and blend until smooth.

Pour the corn milk through a strainer or colander lined with cheesecloth, a little at a time so it doesn't overflow. Stir and press the corn solids so that you get as much liquid from them as possible. When you have most of the liquid out, gather together the corners of the cheesecloth and squeeze well to get as much liquid out as possible. (You can also just use a fine strainer, but it's easier to squeeze all the liquid out using the cheesecloth.)

Place the strained corn milk in a wide, relatively large pot with the sugar and stir to help the sugar dissolve. Place over a medium heat and bring to a simmer, stirring to dissolve the sugar.

Divide the mixture between individual dishes and serve warm, or chilled, topped with a sprinkle of cinnamon.