Peel and chop the potatoes into 1-inch pieces. Place in a large pot, cover with cold salted water, and bring to a rolling boil. Boil for 15-20 minutes until fork-tender.

While potatoes cook, gently warm the milk/cream and cube the butter and cream cheese.

Drain potatoes thoroughly and return to the warm pot. Add butter, cream cheese, salt, and white pepper. Mash until smooth.

Gradually add warm milk/cream, whipping until light and fluffy. Cover and set aside to keep warm.

Pat chicken dry and season generously with salt, black pepper, fresh thyme, and lemon zest.

Heat olive oil in a large oven-safe skillet over medium-high heat. Sear chicken for 4-5 minutes until golden brown. Flip and reduce heat to medium.

Add 1 tbsp butter, minced garlic, and shallots (if using) to the pan. Baste chicken with the mixture for 2 minutes.

Transfer skillet to a preheated 400°F oven. Bake for 10-15 minutes until internal temperature reaches 165°F.

Remove chicken from pan and let rest, covered with foil. Do not clean the skillet.

Return skillet to stovetop over medium heat. Deglaze with white wine or stock, scraping up browned bits. Add remaining stock and Dijon mustard. Simmer until slightly thickened. Adjust seasoning with salt and lemon juice.

In a separate pan, combine carrots, water/stock, butter, and salt. Bring to boil, then simmer covered for 8-10 minutes until tender-crisp.

Remove lid and let liquid evaporate. Add honey or brown sugar. Toss continuously over medium-high heat until glossy and caramelized, about 2-3 minutes.

Plate mashed potatoes, top with sliced chicken and pan sauce, and serve carrots on the side.