Season the chicken on both sides with kosher salt and black pepper.

Preheat a medium Dutch oven over medium-high heat. Add the olive oil. When hot, add the chicken to the pan (in batches if necessary), skin side down, and cook until golden brown on each side, 8 to 10 minutes. Remove the chicken from pan. Add the wine and Dijon mustard. Bring to boil, scraping the brown bits of chicken off the bottom of the pan and mixing with the wine. Add the heavy cream and bring the sauce to a simmer. Return the chicken to the pan and season lightly with salt and pepper. Cover the pan and cook, stirring occasionally, until the chicken is fork-tender, 45 minutes to 1 hour.

Transfer the chicken to a serving bowl and cover to keep warm.

In a small bowl, combine the butter with the flour and stir to form a paste. Ladle some of the hot cream from the pot into the butter-flour paste, and stir to combine. Little by little, whisk the paste into the hot cream in the pot. Cook, whisking to combine thoroughly, until the sauce is thickened and coats the back of a spoon, about 5 minutes. Taste and adjust the seasoning with salt and pepper if necessary. Return the chicken to the pan to heat through (if necessary).

Serve the chicken with the pan sauce spooned over the top. Garnish with the parsley.

This is delicious served it with linguine and a simple green salad. Serve with a chilled Chardonnay.