Preheat your oven to 180°C (350°F) and grease a 20 cm (8-inch) square baking pan.
In a large mixing bowl, combine 200 grams of cornmeal, 150 grams of all-purpose flour, 1 teaspoon of baking powder, 1/2 teaspoon of baking soda, and 1 teaspoon of salt.
In another bowl, whisk together 250 ml of buttermilk, 100 grams of melted unsalted butter, and 2 large beaten eggs.
Add the wet ingredients to the dry ingredients and mix until just combined.
Fold in 200 grams of sweet corn kernels (fresh or thawed from frozen) into the batter.
Pour the batter into the greased baking pan and spread it evenly.
Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted in the center comes out clean.
Allow the cornbread to cool in the pan for 10 minutes before transferring it to a wire rack to cool completely. Cut into squares and serve.