Preheat the oven to 400 degrees F.
First, get the cast iron skillet nice and hot and add the bacon. Fry up the bacon to your desired doneness and remove to a plate and roughly chop the strips.
Next, place the chicken thighs on the skillet. Dust a little salt on each side and pan-fry each side for 5 minutes. We're looking for a sear on each side for now (they'll cook through in the oven later). Once seared, remove to a plate as well.
Now, let's saute your carrots, mushrooms, and onions. I like to add them into the pan in that order. I prefer giving a little space for each ingredient to cook before adding the next. Make sure they are getting some good, brown bits in the pan and the carrots are soft. This should take about 10 minutes.
Add the vinegar, white wine, oregano, parsley, rosemary, salt (1 tsp), and red pepper flakes (if desired).
Stir the mixture, then nestle the chicken thighs back into the pan. Add the bacon.
Place the skillet into the oven. Now let it cook for 30 minutes.
In the last 5 minutes, pull the whole thing out of the oven and dust the flour over the chicken and sauce, and stir to incorporate. (Don't drop all the flour in clumps. The flour will turn into lumps and it will turn into a gross sauce situation.) I like to flip the thighs over in the sauce a bit to spread the flour throughout the mixture. This will help to thicken the sauce.
Pop it back in the oven for the last 5 minutes, or until the chicken is cooked through. (Check with a meat thermometer or cut it open to check for pinkness)
Finally, remove the rosemary, adjust the salt to taste, and serve up with some crusty bread!!