Arrange the chicken in a baking pan / casserole. If using bigger pieces of chicken, make small cuts on several areas on the surface, in order for the marinade to absorb well.
Add the oil, salt, pepper, harissa, mediterranean seasoning and paprika and rub well into the chicken.
Arrnage the lemon slices, filling the gaps in the casserole and place a few under the chicken pieces too.
Preheat oven to 375F.
Cover casserole with foil and place in the oven. Let cook this way for 15 mins or so.
Remove foil and place it back in the oven. Bake till chicken is done all the way through. A thermometer should read 165F when placed into the chicken, near the bones, if you are using bone-in chicken pieces.
Remove from oven. Let rest for 5 mins or so. Serve hot.
Mix salt, garlic powder, basil, oregano, cinnamon, black pepper, parsley, rosemary, dill, marjoram, cornstarch, thyme, and nutmeg in a bowl. Store in an airtight container. Alternately, blend spices in a spice grinder for a finer texture.