First, caramelize the onions. Heat the butter in a large skillet over medium high heat, then add the onions. Turn the heat to medium and let the onions cook for 8-10 minutes. Every couple of minutes, add a tablespoon of water to keep the bottom from burning the onions. Stir them often and let the onions become a lovely golden brown color. Set them aside when they are done. Meanwhile, make the burger patties. Combine the ground chicken, onion soup mix, Dijon, cumin, garlic powder, salt and pepper in a bowl and work it all together thoroughly with clean hands. Either have your grill heated up or heat an indoor electric griddle to 375. Form the mixture you made into 6 equal patties.
Cook the burgers for 5 minutes on each side to get a nice crust on the outside and cook the chicken all the way through. On the second side, add the cheese and cover the burgers so that it melts nicely. When the burgers are done, place them on the toasted buns and top them all with a generous heap of the caramelized onions. Finish with ketchup, HP sauce, mayo, or mustard, whichever you like. Serve immediately with your favorite sides and enjoy!!