Preheat the oven to 375°F (190°C). Meanwhile, lightly grease a 9×13-inch baking pan with butter or oil.
In a spacious mixing bowl, combine all-purpose flour, cornmeal, sugar, baking powder, and salt. Mix these ingredients together until they are well blended.
In a separate bowl, whisk together eggs, milk, and vegetable oil until they are thoroughly combined.
Pour the wet mixture into the dry mixture a little at a time. Stir gently until all ingredients are incorporated, being careful not to overmix as this can result in dense and tough cornbread.
Transfer the batter onto the prepared baking pan and use a spatula to smooth the surface. Place it in the preheated oven and bake for 30-35 minutes or until a toothpick inserted in the center comes out clean.
Once done, remove from the oven and let it cool for 10-15 minutes before slicing and serving.