Heat a large heavy-bottomed Dutch oven or deep skillet over medium-high heat. Add 2 tbs butter. When foaming, add chicken breasts skin-side down and sear 4–5 minutes until golden brown. Flip and sear the other side 3 minutes. Transfer chicken to a plate.

Sauté aromatics

Reduce heat to medium. Add the quartered onion, carrots, and celery to the pot. Sauté 4–5 minutes until vegetables begin to soften and onions are translucent. Add the minced garlic and cook 30 seconds until fragrant.

Deglaze and build pot liquid

Stir in 1 tbs tomato paste and cook 1 minute. Pour in 1 cup dry white wine (or extra stock) to deglaze, scraping up browned bits from the bottom. Let simmer 1–2 minutes to reduce slightly.

Combine and simmer

Return the seared chicken to the pot, placing breasts on top of the vegetables, skin-side up. Add 2 cups chicken stock and 2 bay leaves plus the rosemary and thyme sprigs. Bring to a gentle simmer, then reduce heat to low, cover, and simmer for 20–25 minutes until chicken reaches an internal temperature of 165°F (74°C) and vegetables are tender.

Finish and rest

Remove chicken to a warm plate and tent loosely with foil. Take out and discard bay leaves and herb stems. Keep the pot juices and vegetables in the pot for making gravy and serving.

Mashed Potatoes

Cook potatoes

Place peeled and cubed potatoes in a medium pot and cover with cold water by 1 inch. Add 1 tsp salt. Bring to a boil, then reduce to a simmer and cook 12–15 minutes until potatoes are tender and easily pierced with a fork.

Drain and mash

Drain potatoes thoroughly and return to the warm pot over very low heat for 1 minute to evaporate excess moisture. Remove from heat. Add 3 tbs butter and warm 3 tbs milk. Mash with a potato masher or ricer until smooth. Season with 1 tsp salt and 1/2 tsp black pepper, adjusting to taste. Keep warm until serving.

Vegetables

Steam or blanch vegetables

While the chicken simmers, bring a small pot of water to boil with a pinch of salt. Add green beans or broccoli and blanch 3–4 minutes until bright and tender-crisp (or steam 4–6 minutes). Drain and toss with 1 tbs butter, seasoning to taste with salt and pepper. Keep warm.

Gravy

Make a slurry

After removing the chicken and herb stems, keep the pot over medium heat. Skim excess fat if desired, leaving about 1 tbs in the pot. In a small bowl, whisk 2 tsp flour with 2 tbs cold water until smooth to form a slurry.

Thicken the sauce

Bring the pot juices to a gentle simmer and slowly whisk in the slurry. Cook 2–3 minutes, whisking constantly, until the gravy thickens. If too thin, make another 1 tsp flour + 1 tbs water slurry and add a little at a time. Taste and season with salt and pepper as needed. If you prefer a smoother gravy, strain the sauce through a sieve into a small saucepan and simmer briefly before serving.

Finish

Return the chicken to the pot briefly (skin-side up) to warm through in the gravy for 1–2 minutes if desired, then serve.