In a large bowl, combine the precooked cornmeal and salt. Gradually add the warm water, whisking to remove any lumps, until a combined mixture forms. Let the mixture rest for 5-10 minutes.

Using your hands, divide the dough into 8 equal pieces. Roll each piece into a ball and gently flatten it into a disk, about 1 inch thick.

Heat a thin layer of oil (about 0.25 inches deep) in a large, heavy skillet over medium heat. Add the corn cakes to the hot oil and fry for about 6 minutes on each side. The cakes should develop a dry, fried exterior without becoming overly brown. Transfer the cooked cakes to paper towels to drain and cool.

Once cooled slightly, carefully cut each corn cake in half horizontally. Stuff with your desired fillings and serve immediately.