Rinse & pat dry chicken thighs & season with salt & pepper. In a large cast iron pan over medium-high heat, add 1 tbsp olive oil & brown chicken thighs on both sides. Transfer to a plate.
In the same pan, sear lemon slices until nicely browned on one side. Transfer to the plate with the browned chicken thighs.
In the same pan, heat remaining 2 tbsp olive oil & combine garlic, zucchini & orzo & cook for 3-4 minutes, stirring often. Add in chicken broth, Italian seasoning, bay leaf, salt & pepper & stir well.
Return chicken thighs & lemon slices back to pan & transfer to preheated oven. Cook uncovered for 15-20 minutes until orzo is tender & chicken is cooked through. Finish with fresh chopped parsley, lemon zest and salt & pepper to taste.