Cook mushrooms:
In a separate pan, heat 1 tablespoon vegetable oil. Add sliced mushrooms and cook on high-medium heat for 1-2 minutes until mushroom caramelize. Do not salt mushrooms or it will prevent the caramelization.
Smothered chicken assembly:
Remove the chicken breasts from the oven (you baked them for 15-20 minutes). Top each chicken breast with the creamed spinach, chopped cooked bacon, cooked mushrooms and broken slices of pepper jack cheese. Bake in the oven, uncovered for 15-20 more minutes, until chicken is cooked through, no longer pink in the center, and the juices run clear. Broil for the last 2-4 minutes, if desired, being careful not to burn the cheese on top.
