How to boil maize(Indian corn)

Flint corn has a very hard outer layer to it. If it's mature and dried, you may need to simmer it for some time, then attempt to work the hull off.

There was an episode of 'My Grandmother's Ravioli', where they made an indian corn soup. The recipe posted online calls for nixtamalization:

Remove the corn kernels from each ear by using your thumb to push kernels up and off the cob. Heat a large cast-iron pot over medium-high heat. Add the kernels, the hardwood ash and water to cover by 4 inches. Bring to a boil and cook for 1 hour, or until most of the hulls have fallen off the kernels. Strain through a drying screen or colander. Rinse the corn with fresh water until all the ash is removed and the water runs clear.