In a bowl, combine the sauce ingredients (mayo, ketchup, mustard, and hot sauce) and mix well. Set aside.

Preheat your grill on high heat. Make sure the grates are clean and well-oiled to prevent sticking.

Slice the sweet onions into thin rounds. Heat a skillet over medium-high heat and add a tablespoon of oil. Once the oil is hot, add the sliced onions and cook for about 10-12 minutes, or until they are tender and lightly caramelized. Stir occasionally to prevent burning. Season the onions with salt and pepper to taste, then remove from heat and set aside.

In the same skillet, cook the bacon over medium heat until crispy. Remove from heat and set aside.

Take the patties and season both sides with salt and pepper. Place them on the grill and let them cook for 3 minutes. Flip the patties and cook for another 2-3 minutes until they are cooked through. During the last minute of cooking, place a slice of cheddar cheese on top of each patty and close the grill lid to melt the cheese.

Once the patties are done, remove them from the grill and place them on a plate to rest.

While the patties are resting, toast the buns on the grill for about 10-15 seconds. Remove them from the grill and set aside.

To assemble the burgers, spread the sauce on the bottom bun. Then add a layer of the caramelized onions and a few strips of crispy bacon. Top with two patties with melted cheddar cheese. Add another layer of sauce, then top it off with the other half of the bun.

Repeat with the remaining ingredients to make the remaining burgers.

Serve hot with your favorite side dishes, such as fries or a salad.