Preheat the oven to 375°F. Place a 9x9 inch cast iron skillet in the oven while the oven is heating up.
Mix together the dry ingredients. Add all-purpose flour, yellow cornmeal, salt, baking soda, and baking powder to the bowl. Mix until combined. Set aside.
Reserve 1 tbsp butter for greasing the skillet. Melt the remaining butter in a microwave-safe bowl.
In a large mixing bowl, whisk together melted butter, vegetable oil, granulated sugar, and honey. Add eggs and buttermilk. Whisk until combined.
Add the dry ingredients to the wet. Stir until just combined and no large lumps of flour remain. Don't over-mix the batter.
Remove the skillet from the oven. Grease the preheated cast iron skillet with reserved 1 tbsp of butter. Then, pour the batter into the greased skillet. Bake in the preheated oven for 25-30 minutes or until ready. Check the readiness of the homemade cornbread using a toothpick inserted in the center, if it comes out clean - the cornbread is ready. Remove the cast iron skillet from the oven and let the homemade cornbread cool for 5-10 minutes. Then, slice and serve.