Preparation

1. Preheat the oven to 400°F (200°C).
2. Pat the chicken thighs dry with paper towels and season with salt and pepper.
3. Slice mushrooms thickly, chop onion, mince garlic, and halve baby potatoes.
4. If using bacon, cut it into small pieces and cook in a skillet until crisp. Set aside and leave some fat in the pan.

Browning Chicken

1. Heat the skillet over medium-high heat, add oil if needed, and place the chicken skin-side down.
2. Brown the chicken for 6-8 minutes without moving it, until golden. Flip and brown the other side for 2-3 minutes.
3. Remove the chicken from the skillet and set aside.

Making the Sauce

1. In the same skillet, add chopped onion and mushrooms, cooking until slightly browned.
2. Add minced garlic for about 30 seconds, then stir in tomato paste and let it cook for another minute.
3. Pour in the red wine, scraping up any browned bits from the bottom of the pan. Simmer for a few minutes.
4. Add chicken broth, thyme, and Dijon mustard, stirring to combine.

Combining and Baking

1. Add halved potatoes to the sauce and toss to coat.
2. Nestle the browned chicken thighs on top skin-side up.
3. Cover with a lid or foil and bake for 35 minutes.
4. Remove the lid/foil and bake for an additional 10-15 minutes until the skin is crisp and the sauce has thickened.

Checking for Doneness

1. Ensure the chicken is cooked to an internal temperature of 175°F to 185°F.
2. Check potato tenderness by piercing with a fork; it should slide in easily.
3. If potatoes are firm, remove the chicken and keep baking potatoes until tender.