Start by preheating your oven to 425°F (220°C). If you’d like to make cleanup easier, line a baking sheet or casserole dish with parchment paper, but this step is optional.

In a bowl, combine the feta, mozzarella, chopped black olives, sun-dried tomatoes, avocado oil, garlic powder, kosher salt, red pepper flakes, and black pepper. Stir everything together until well mixed, then give it a quick taste to adjust the seasonings to your liking.

Place the chicken thighs on your prepared baking sheet or in a casserole dish. Find the natural opening where the skin connects to the meat and gently widen it with your finger to create space for the stuffing.

Fill each thigh with the stuffing, using a spoon or your hands to pack it in. Don’t worry about piling it up—the skin will hold the filling nicely as it bakes.

Once stuffed, place the dish in the oven and roast for about 25 minutes, or until an instant-read thermometer inserted into the thickest part of the meat reaches 165°F.

Let the chicken rest for about 5 minutes after removing it from the oven. Serve alongside your favorite Mediterranean-inspired sides and enjoy!