Mine is sweet as well, but I don't see why you couldn't just leave the sugar out, frankly. It's from the America's Test Kitchen cookbook. I'll give you it sans sugar.
1 1/2 cups plain flour
1 cup yellow cornmeal
2 tsp baking powder
3/4 tsp salt
1/4 tsp baking soda
1 cup buttermilk
3/4 cup frozen corn kernels, thawed
2 large eggs
8 tbsp melted butter, cooled (or half of one of those 250g slabs)
Adjust an oven rack to the middle position and heat the oven to 200 degrees Celcius. Generously coat an 8-inch square baking pan with vegetable oil spray. Whisk the flour, cornmeal, baking powder, salt and baking soda together in a large bowl. Process the buttermilk, corn, and eggs in a food processor until combined, about 5 seconds. Gently fold the buttermilk mixture into the flour mixture, then fold in the melted butter until just combined (batter will be thick). Scrape the batter into the prepared pan and smooth the top. Bake until deep golden brown and a toothpick inserted into the center comes out with just a few crumbs attached, about 35 minutes. Let the cornbread cool in the pan for 10 minutes before unmolding onto a wire rack to cool for 10 minutes.
N.B. I do this in a bundt pan instead, and you just have to watch it and test it for time. Baking time varies by oven anyway. If you DID want the sweet version, you add 1/4 cup brown sugar to the egg/corn/buttermilk mixture in the food processor.