Prepare all of the ingredients. Preheat oven to 450deg. Preheat Grill or Grill Pan to medium high. Preheat oil to medium high.
Combine ingredients for sauce in a bowl and place in refrigerator until ready to make burgers.
In a frying pan over medium high heat, add strips of bacon. Cook until crispy and remove to paper towel covered plate.
In a bowl, combine burger ingredients. Form into 8 patties, about 4 inches in diameter. When grill or grill pan is heated, cook on each side for 7-8 minutes. Remove from grill and place slice of cheese on top.
Melt butter and add garlic powder and parsley. Place buns on baking sheet face up and brush with butter mixture. Place in oven for 12 minutes to toast.
While burger are cooking, combine corn starch, salt, and paprika. Then add onions and toss to coat. Once oil is hot, add onions in small batches. Fry until golden brown (1-3 minutes) and remove to a metal rack positioned over paper towels.
Build the Burger: Toasted bottom bun spread with sauce, cheese burger, 2-3 pieces bacon, fried onions, and toasted Top Bun spread with sauce.