Balsamic-Braised Chicken (Revised)

I finally got around to making this and while it was good, I've made some changes to make it even better.  First, leave out the chard and serve over mashed potatoes with a side of steamed green beans. 

Second, it needs more liquid so bump the chicken stock up to 1 1/2 cups. And finally, I don't know how you could get 12 bone-in chicken thighs into this-- totally too much chicken. I used 6 boneless, skinless chicken thighs and it was just the right amount. 

The sauce is just delicious and goes over mashed potatoes like it was made for it. 

Balsamic-Braised Chicken with Swiss Chard

1 tablespoon extra-virgin olive oil
1 onion, minced
5 teaspoons minced fresh thyme, or 1 1/2 teaspoons dried
1 tablespoon tomato paste
3 garlic cloves, minced
1 anchovy fillet, minced
1/4 teaspoon red pepper flakes
3 tablespoons all-purpose flour
1/2 cup balsamic vinegar
1 (14.5 ounce) can diced tomatoes, drained
1/2 cup low-sodium chicken broth (1 1/2 cups)
1/4 cup dry red wine
2 bay leaves
12 bone-in chicken thighs, skin removed, trimmed (6 boneless, skinless)
Salt and pepper
6 ounces Swiss chard, stemmed and leaves slices 1/2 inch thick (leave this out)

Heat oil in 12 inch skillet over medium-high heat until shimmering.  Add onion, thyme, tomato paste, garlic anchovy, and red pepper flakes and cook until onion is softened and lightly browned, 8 to 10 minutes. Stir in flour and cook for 1 minute. Slowly whisk in vinegar, scrapping up any browned bits and smoothing out any lumps; cook until slightly reduced, about 3 minutes, and transfer to slow cooker.  

Stir tomatoes, broth, wine, and bay leaves into slow cooker. Season chicken with salt and pepper and nestle into slow cooker. Cover and cook until chicken is tender, 4 to 6 hours on low. 

Gently stir in chard, and cook on high until tender, 30-45 minutes.  Transfer chicken to serving platter and tent loosely with aluminum foil. Let braising liquid to settle for 5 minutes, then remove fat from the surface using a large spoon. Discard bay leaves.  Season with salt and pepper to taste.