Preheat the oven to 375 degrees F.
Pat the chicken thighs dry with a paper towel to absorb any excess moisture.
Season both sides of the chicken with salt and pepper.
Heat a cast iron skillet or oven safe pan on the stove over medium high heat.
Add the olive oil to the skillet or pan.
Place the chicken thighs in the skillet, skin side down. Cook for 5 minutes per side or until the chicken is golden brown.
In a bowl, mix together the cranberries, orange zest, orange juice, maple syrup, minced garlic, and chopped rosemary.
Pour the cranberry mixture over the chicken thighs in the skillet, then transfer the skillet to the oven.
Bake for 25-30 minutes, until the chicken is cooked through and the cranberries have burst.
Spoon the cranberry sauce over the chicken thighs, then serve. Garnish with rosemary sprigs and orange slices if desired.