Coat a 9 or 10-inch cast iron skillet with a layer of vegetable or olive oil.
Be generous with the coating of oil since you don't want the cornbread to stick when trying to remove it.
When oven is finished preheating, place the skillet into the oven to warm up (for about 6-8 minutes.)
While skillet is warming up, prepare the cornbread batter.
In a large bowl, mix together both packets of cornbread mix with water and egg.
Finely chop basil and sun-dried tomatoes.
And cut mozzarella balls in half.
Add basil, mozzarella and sun-dried tomatoes to cornbread batter.
Stir gently until combined.
When skillet has warmed, add cornbread batter to the skillet.
Bake cornbread (on middle oven rack) for approximately 15 to 20 minutes (until golden brown.)
Notes
Please be careful removing the cast iron skillet from the oven. It is heavy and hot so use oven gloves and take care. Slice and serve while warm! This cornbread reheats really well too.