Preheat your oven to 375°F (190°C). Grease a 9-inch square baking dish or cast-iron skillet.
In a large mixing bowl, combine the cornmeal, flour, baking powder, baking soda, and salt. Whisk together until well incorporated.
In a separate bowl, whisk together the sugar, honey, egg yolk, eggs, melted butter, oil, and buttermilk until smooth.
Pour the wet ingredients into the dry ingredients and stir until just combined. Be cautious not to overmix; a few lumps are cool.
Pour the batter into the prepared baking dish or skillet, spreading it evenly. (I like to let it sit for about 10 minutes, optional)
Bake for 25-30 minutes or until the top is golden brown, and a toothpick inserted into the center comes out clean.
Allow the cornbread to cool for 10-15 minutes before slicing and serving.