Combine ground chuck, salt, and Sweet Black Pepper Sauce in a bowl and mix. Form into 4 patties. Sprinkle patties with Beef Rub.
Grill burgers on a medium hot grill for about 5 minutes per side or until desired degree of doneness. Top with cheese slices just before removing from grill.
To make onion rings. whisk together flour, cornstarch, baking powder, salt and pepper in a large bowl.
In a medium bowl, whisk egg whites until light and frothy. Whisk in beer and water.
Add liquid ingredients to dry and whisk just until combined.
Heat about 2 inches of Vegetable oil in a Dutch oven to 375 degrees.
Separate onions into rings and dip in batter.
Fry in batches until golden brown. Drain on a paper towel-lined baking sheet and season lightly with salt.
Pile burgers, lettuce, and bacon on buns. Top with 2 to 3 onion rings and bbq sauce and serve.