In a skillet, saute the onion and garlic in oil until softened. Add ketchup and 1/2 cup of water. Bring to a boil, the lower the heat and simmer 5 minutes. Add the remaining ingredients and simmer until thickened, 10-15 minutes longer. Off heat, use an immersion blender to puree until smooth. Alternately, use a food processor or standard blender.

Place the chicken into a crock pot on the low setting. Add 1 cup of Hot Honey BBQ Sauce plus 1/2 cup of water at a time until the chicken is coated and saucy. Cook 4-6 hours, then use forks to pull the chicken apart into long strings.

Peel and slice the onion crosswise as thinly as possible. Separate into rings. Pour buttermilk into a shallow bowl. In a separate shallow bowl, combine the flour, salt, pepper and cayenne.

Heat oil over medium heat in a large nonstick skillet. Dredge each onion ring in the buttermilk, then the flour mixture, and drop into the skillet. Flip after 2-3 minutes so that both sides are golden brown. Remove onion rings to a paper towel-lined plate. Keep warm.

Slice the bread into 1 inch-thick slices and butter on both sides. Grill over medium heat until both sides are crisp and golden. Pile the pulled chicken and onion strings in between two slices of grilled bread.