Step 1

Pour vegetable oil into a 9-inch cast iron skillet and place skillet in the center of the oven. Preheat oven to 400 degrees F (200 degrees C).

Step 2

While the oven is preheating, place corn in a microwave-safe bowl. Cover and microwave on high for 2 1/2 minutes, stirring halfway through. Place corn in a colander to drain any excess liquid, then transfer to a medium bowl. Add blueberries and 2 tablespoons flour and toss to combine; set aside.

Step 3

Combine cornmeal, 1 cup flour, sugar, baking powder, and salt in a large bowl.

Step 4

Whisk buttermilk, melted butter, and eggs together in a small bowl. Pour into the cornmeal-flour mixture and mix to combine. Gently fold in the reserved blueberry-corn mixture.

Step 5

Remove skillet from the oven and brush the oil onto the bottom and sides until coated. Pour batter into the hot skillet and level the top with a spatula.

Step 6

Bake in the preheated oven until golden brown and a toothpick inserted into the center comes out clean, 25 to 30 minutes. Serve warm.