Cut onions into 1/2 inch thick rings. Soak onions in cold water for 15 minutes.
While onions soak, mix together cornbread mix according to directions on the back of box.
Place 1 cup of flour in separate bowl. In a deep fryer or a large skillet pour in 2 inches of peanut oil. Bring oil up to 350° F.
Dip onion rings in flour and then into cornbread mixture. Drop several onion rings in at a time but make sure they are not touching.
Fry on both sides until golden brown.