Gluten Free Skillet Cornbread - Delicious!

Sometimes the best things  are spur of the moment recipe alterations.  This started out as a muffin recipe I had developed years ago.  I head read about cornbread today and it stuck in my mind so 15 minutes before supper I decided to give it a go. 
This is a very simple recipe that goes great with most meals.  If you prefer a recipe using corn flour go to this link: http://applewoodrecipes.blogspot.ca/2014/10/gluten-free-skillet-corn-bread-with.html
Gluten Free Skillet Cornbread! 
1 cup milk
1 egg
1/4 cup cooking oil - I used canola

1/4 teaspoon vinegar
1/2 cup cornstarch
1/2 cup tapioca starch
1/2 cup rice flour
1/2 cup cornmeal
2 tbsp. sugar
1 tbsp. baking powder
1 tsp salt
1/4 tsp. baking soda
1/2 guar gum
Preheat oven to 425 F.
Mix milk, egg, oil and vinegar together in a mixing bowl using a fork or wisk.
Add remaining ingredients and stir well with a wooden spoon.
Heat a 10.5" cast iron skillet over high heat and melt 1 tablespoon butter in skillet.  Pour batter into hot skillet.  Fry for about 3 minutes until edge starts to look set.  Using a oven mitt grab handle of skillet and place into hot oven.  Bake an additional 10-12 minutes or until toothpick inserted in center comes out clean.  Serve warm with butter.
Notes:  You could also butter a 10" baking pan and bake it in there for 15-20 minutes until done.