Preheat your oven to 180°C (350°F).
Take the chicken thighs and season them generously with salt and pepper on both sides.
Heat a pan over medium-high heat.
Place the seasoned chicken thighs in the pan and sear them for about 4-5 minutes on each side, until they are golden brown.
Ensure each side is cooked evenly to achieve a crispy texture and seal in the juices.
Once browned, remove the chicken thighs from the pan and set them aside on a plate.
In the same pan that you used for the chicken, add chopped bacon and cook until it becomes crispy.
Once cooked, remove the bacon and set it aside for later.
Add diced onions and minced garlic to the pan. Sauté until they are soft and translucent.
Stir in sliced mushrooms and continue cooking until they soften and reduce in size.
Add a generous pinch of fresh thyme leaves to the mixture for added flavor.
Add tomato puree, Worcestershire sauce, chicken stock, and a pinch of brown sugar to the pan.
Stir well to combine all ingredients and let the sauce simmer for a few minutes to meld the flavors.
Taste the sauce and adjust seasoning if necessary, adding more salt or black pepper to your preference.
Return the seared chicken thighs to the pan, ensuring they are fully coated in the tomato sauce.
If using, transfer the mixture to a cast-iron pan (if not already in one).
Cover the pan with a lid or aluminium foil.
Place the covered pan in the preheated oven and bake for 25-30 minutes, or until the chicken is cooked through and the sauce has thickened.
Before serving, check that the chicken is fully cooked by slicing into the thickest part of the thigh. The juices should run clear, and the meat should no longer be pink.