Season the chicken thighs with the salt and pepper and half the fresh or dried rosemary.
Heat 1 tablespoon of olive oil in a skillet over medium heat. Brown the chicken thighs for about 5 minutes on each side. Remove from the skillet and keep warm.
Add the remaining tablespoon of olive oil to the pan, increase the heat under the skillet and add the tomatoes and garlic. Stir to combine. Add a pinch of salt and pepper and red pepper flakes and cook until the tomatoes begin to burst, about 5 minutes. Stir in the sherry and lemon juice scraping up any brown bits from the pan bottom. Add the Chicken broth and the rest of the rosemary and bring to a boil.
Return the chicken thighs to the pan, turn the heat to a low simmer, cover and cook for 30 mins. or until a knife inserted into the chicken thighs release juices that run clear. Adjust salt and pepper to taste.
Garnish with lemon zest and Serve with your favourite sides.