In a large bowl, sift together 1 cup flour, cornmeal, baking powder and salt.
In a separate bowl, whisk together milk, oil, egg, sugar and baking soda. Gently fold wet ingredients into dry ones until just combined.
Carefully coat the blueberries with the 2 tablespoons flour and fold them into the batter along with the corn and cheese.
Melt butter in a 9-inch cast-iron skillet over medium-high heat, making sure to coat bottom and sides completely. Cook butter 2 to 3 minutes, until it starts to color and smell nutty. Scrape batter into skillet.
Place skillet in oven and bake until bread is golden and a toothpick inserted in center comes out clean, 30 to 35 minutes. Let cool 5 minutes. Cut into wedges and serve.