http://ohsheglows.com/2012/02/28/crispy-baked-onion-rings/

1 large sweet onion 2/3 cup flour of choice 2/3 cup + 1 tbsp vegetable broth 2 tbsp cornstarch (or arrowroot flour) 1/2 cup cornmeal 1 cup breadcrumbs 1/4 cup nutritional yeast (optional, but recommended) 3/4 tsp kosher salt 1-2 tbsp black sesame seeds (optional) 1 tsp garlic powder 2 tsp dried herbs (I used 1tsp each basil & oregano)

Preheat oven to 425F and line a large baking sheet with parchment paper or spray with cooking oil. Slice onion into rings, 3/4 inch in width (larger than shown in pictures as I made mine too thin), and reserve about 15-22 or so, wrapping up the leftovers for another use. In a shallow dish, whisk together the batter ingredients (flour, broth, cornstarch). In another shallow dish, whisk together the coating ingredients (cornmeal, breadcrumbs, nutritional yeast, salt, sesame seeds, garlic powder, and herbs). With a fork, dip an onion ring into the batter, coating all sides. Now transfer it to the coating mixture and toss it around a bit. Use a clean & dry hand to scoop up coating and sprinkle it all over the ring. If at any time your hands get sticky or coated, simply rinse and dry before starting again. Place onion rings on prepared baking sheets and repeat for the rest. Don’t worry if things get messy or they don’t coat “perfectly”…just consider them rustic and call it a day! You will have coating leftover that isn’t used up. Bake for about 18 minutes at 425F, flipping once after 10 minutes. You can broil them for a minute or two at the end to brown. Serve with your favorite dip or ketchup. These are best served immediately.