Heat olive oil in a heavy skillet over medium-high heat until shimmering.

Season chicken thighs with salt and pepper and place skin-side down in the skillet. Sear for 5-7 minutes until golden brown.

Flip the thighs and sear the other side for an additional 5 minutes.

Transfer the chicken to a plate and set aside.

In the same skillet, add diced shallots and sauté for 2-3 minutes until soft and translucent.

Pour in dry white wine, scraping up browned bits and allowing to reduce for 2 minutes.

Whisk in Dijon mustard and heavy cream until combined; cook for 2-3 minutes to thicken.

Return chicken to skillet, skin-side up, and simmer for 10-15 minutes, basting occasionally.

Taste and adjust seasoning with salt and pepper as needed; garnish with fresh tarragon.

Serve the chicken with creamy sauce drizzled on top; ideal with mashed potatoes or a salad.