Baked Cayenne Buttermilk O-Rings with Cayenne Greek Yogurt Sauce

3/4 cup buttermilk
1 large sweet onion, sliced about 1/2 thick rings (reserve 12 large rings)
1 Bag Crunchmaster  Rosemary/Olive Oil Crackers (4.5 oz), ground
3 TBS olive oil
2 cups gluten free flour (reserve 1 cup)
2/3 cup tonic water
1 tsp cayenne pepper, reserve half for sauce
1 cup Greek Yogurt
3 TBS brown sugar
2 TBS sea salt

Directions:

1.  Peel and slice onion.  Place in large bowl and cover with buttermilk.  Let sit while preparing other steps.  Toss to coat, occasionally. 
2.  Add ground cracker crumbs and oil in bowl.  Toss to blend.  Add 1 cup flour to separate bowl.  Put aside.
3.  In separate bowl add remaining 1 cup flour, tonic, 1/2 tsp cayenne pepper and buttermilk from onions.  Mix well.
4.  Preheat oven to 350 degrees
5.  Spray two large cookie sheets with cooking spray.
6.  Dredge onion slice into flour, then into batter, then into crumbs.  Make sure to evenly coat inside and both sides of onion slices so each ingredient adheres.  Place on cooking sheet.  Repeat process with other rings.
7.  Bake for 10 minutes, then flip and bake for additional 10 minutes.  Season with sea salt.
8.  For sauce:  Mix yogurt, sugar, 1/2 tsp cayenne pepper.  Season with salt, to taste.

Makes about 12 large rings.  Serves approx. 4