Heat olive oil in a skillet over medium heat. Season chicken thighs with salt, pepper, and mixed herbs. Sear thighs until golden brown, about 5 minutes per side.
Reduce heat and add heavy cream to the skillet, simmering until the chicken is cooked through and the sauce thickens.
Peel and chop potatoes. Boil in salted water until tender. Drain and mash with milk and butter until smooth.