2boneless skinless chicken breastscut in half lengthwise
Sea salt and pepperto taste
Garlic powderto taste
1tbspbalsamic vinegar
2tbspDijon mustard
1/2-1cupGruyeregrated
Instructions
Melt the butter in a large Dutch oven over medium heat, add the onions and cook until deeply golden brown, about an hour, stirring often, adding a bit of beef broth to deglaze the pan as needed.
Preheat the oven to 350 degrees
Add the garlic, thyme, and flour to the onions then cook for another minute, stirring constantly. Add one cup of the beef broth, deglaze the pan making sure to scrape up any browned bits on the bottom of the Dutch oven, bring to a boil, reduce the heat and simmer for 5 minutes.
Meanwhile, heat the oil in another large skillet over medium-high heat. Cut each chicken breast in half lengthwise (and the thin ends off if you'd like) season each piece of the chicken evenly with sea salt, freshly cracked pepper, and garlic powder, to taste. Add the chicken to the hot pan and brown on both sides, about 3-4 minutes per side, set aside on a plate.
Add the remaining cup of broth to the large skillet that you cooked the chicken in, deglaze it making sure to scrape up any browned bits off the bottom of the pan, whisk in the balsamic vinegar and mustard, bring it to a boil, then reduce the heat and simmer to reduce the sauce by half, about 5 minutes.
Pour the vinegar/mustard sauce on the onions and mix well to combine. Add the chicken and its juices to the onions then spoon sauce over each piece. Cover with a lid and bake in the oven for 10 minutes.
Remove the chicken from the oven and sprinkle the top with the cheese. Place back into the oven under the broiler until the cheese has melted, about 2-4 minutes. Sprinkle the top with fresh thyme leaves, if desired, and serve. Enjoy.