Start by cooking the bacon in a large skillet over medium heat until crispy. Once done, place the cooked bacon on a plate lined with paper towels to drain the grease. Crumble the bacon and set it aside. Leave the bacon drippings in the skillet for extra flavor.
Preheat your oven to 350°F (175°C). Spray a 9×13-inch baking dish with nonstick cooking spray to make cleanup easier.
Season your chicken tenders with salt and a pinch of pepper. Coat the chicken pieces lightly in all-purpose flour. This gives the chicken a golden crust when cooked.
Heat the leftover bacon grease (or 2 tablespoons of vegetable oil) in the skillet. Add the chicken tenders and cook over medium heat until they’re lightly browned on both sides. Transfer the chicken to the prepared baking dish, arranging the pieces in a single layer.
Using the same skillet, sauté the sliced onions until soft and caramelized, about 5 minutes. Spread the onions over the chicken in the baking dish.
Mix the cream of chicken and mushroom soup with 1/2 cup of water (or milk) in a bowl. Pour the mixture evenly over the chicken and onions in the baking dish.
Place the dish in the preheated oven and bake uncovered for 25–30 minutes or until the chicken is fully cooked (internal temperature of 165°F).
Remove the dish from the oven and sprinkle the shredded cheese and crumbled bacon on top. Return it to the oven for another 5–7 minutes, or until the cheese is melted and bubbly.
Serve the smothered chicken hot over white rice, mashed potatoes, or with roasted vegetables on the side.