Using a large oven proof stock pot, over medium heat begin by browning the bacon. Cut it into small pieces (lardons). Sauté until the bacon is crispy and you've rendered all of the fat from the bacon. Remove the bacon from the pan & drain on paper towels. Retaining the bacon fat.
Next sprinkle the chicken thighs with half of the salt & pepper and brown in the stock pot. You may need to add more oil to the pan (I used olive oil). Brown both sides, about 5 minutes side one & 3 on side two. When both sides are brown, remove and set aside.
Add the carrots, onions, celery and tomatoes to the pan - saute' them for 4 minutes until they just begin to soften. Add in the garlic and continue to saute' for another minute. After 5 minutes, add the remaining salt & pepper, thyme, red pepper flakes, bay leaf & tomato paste and saute' for another minute. Next add the beer and scrape the bottom of the pan well to release all of those good bits of flavor on the bottom. Add in the chicken stock, bacon and beans. Stir well and tuck the chicken thighs into the stew. Cover tightly & into the oven it goes. Bake at 325 degrees for 1 hour 15 minutes.
Take the pot of stew out the oven & place it on the stove. Remove the chicken thighs and set them aside to cool. When they are cool enough to handle, shred the meat well, using clean hands or a couple of forks. I usually go one step further and chop the meat also (so it will easily fit on your soup spoon). Add the shredded meat back to the stock pot and discard the bones. Remove & discard the bay leaf.