Several hours to a day ahead, season the chicken breasts with salt, cumin, garlic powder, pepper and chipotle chili powder. Cover and let marinate in the fridge.
In a large skillet, cook bacon over medium-high heat until crisp on both sides. Turn off the heat and remove the bacon from the pan. Let the bacon strips drain and rest on paper towels while you cook the chicken.
In the pan you cooked the bacon in, remove all but about 1-2 tablespoons of bacon grease. Turn the heat back to medium-high and brown the chicken on both sides. Approximately 4-6 minutes each side, depending on thickness.
When the chicken is almost completely cooked on the second side, coat with a generous layer of BBQ sauce. Layer 2 slices each of tomato and bacon on top of each piece of chicken. Then pile a handful of cheese on each, then sprinkle with scallions.
Cover the pan if you have a cover that is tall enough or tent aluminum foil over the skillet, or place in the oven under the broiler for a minute to melt or even crisp the cheese before serving.
Serve with extra BBQ sauce on the side.