Preheat the oven to 375°F. Season the chicken breasts with salt and pepper on both sides.
In a large oven-safe skillet, heat the olive oil over medium-high heat. Add the chicken breasts and sear for about 5 minutes on each side until golden brown. Remove the chicken from the skillet and set aside.
In the same skillet, add the chopped bacon and cook until crispy. Remove the bacon with a slotted spoon and drain on paper towels, leaving the drippings in the skillet.
Add the sliced mushrooms to the skillet and sauté for about 5 minutes until they are tender. Stir in the minced garlic and cook for an additional minute.
Pour in the heavy cream and chicken broth, then stir in the Dijon mustard, garlic powder, and red pepper flakes. Bring the mixture to a simmer.
Add the fresh spinach to the skillet and cook until wilted, about 2-3 minutes. Stir in the cooked bacon and half of the Parmesan cheese.
Return the chicken breasts to the skillet, spooning some of the sauce over the top. Sprinkle the remaining Parmesan cheese on top.
Transfer the skillet to the preheated oven and bake for 20-25 minutes, or until the chicken is cooked through (internal temperature of 165°F).
Remove from the oven and let rest for 5 minutes before serving.