Prep the chicken: Pound chicken breasts to even thickness (about ½ inch). Season both sides with salt and pepper.
Cook the bacon: Cook bacon until crispy, then crumble or chop. Set aside.
Sear the chicken: In a large oven-safe skillet, heat 1 tbsp oil over medium-high heat. Sear chicken for 3–4 minutes per side until golden. Remove and set aside.
Sauté the mushrooms (optional): Add a bit more oil if needed. Sauté mushrooms until soft and browned (about 4–5 minutes). Remove from pan.
Make the sauce: In a small bowl, whisk together Dijon mustard, sugar-free honey, mayonnaise, apple cider vinegar, garlic powder, and paprika. Taste and adjust sweetness or tang if needed.
Assemble: Preheat oven to 375°F. Return chicken to the skillet. Spoon sauce over each breast. Top with mushrooms (if using), crumbled bacon, and shredded cheese.
Bake: Transfer skillet to preheated oven. Bake uncovered for 10–12 minutes, or until chicken reaches 165°F internal temperature and cheese is bubbly and golden.
Serve: Let rest 5 minutes before serving. Pair with roasted vegetables, cauliflower mash, or a fresh green salad.