Moist cornbread with a cheddar top.
Preheat oven to 400 degrees F. with the cast iron skillet inside.
In a medium-sized bowl, whisk together the flour, cornmeal, baking soda and salt. Set aside.
In another bowl, whisk eggs to blend together, then add the corn, butter and sugar. Whisk together. Fold in jalapenos and one cup cheese.
Add the wet ingredients to the dry and gently mix until just barely incorporated.
Carefully remove skillet from oven, spray with cooking spray, then scrape in the batter and smooth top. Top with remaining cheese, return skillet to oven and bake until the top is golden brown and the cornbread springs back when gently pressed with a finger, 20 to 25 minutes. Let cool slightly before serving.