Stir in the cornmeal slowly while whisking until all the cornmeal is incorporated.
Continue stirring until the polenta is thick and creamy, about 3 minutes.
Stir in ¼ cup of cotija and 1 teaspoon each of salt and pepper.
Spread the polenta into the baking dish, creating a 1-inch layer.
Bake until firm, about 40 minutes. Let cool completely for at least an hour or overnight.
In the meantime, mix together the corn, crema, lime, remaining cotija, Tajin, and remaining ½ teaspoon salt and pepper.
Using a small biscuit or cookie cutter, cut the polenta into small circles.
Heat the oil in a skillet over medium heat.
Once hot, add the polenta cakes and brown them, about 2 minutes per side.
To assemble, place the crispy polenta cakes on a serving dish and spoon the elote mixture onto them. Garnish with cilantro, sprinkle with extra Tajin, and serve.