Season chicken thighs with salt, pepper and lemon juice.
Heat the olive oil in a skillet over medium-low heat.
Place the chicken thighs skin side down in the skillet and cook for about 10 minutes to crisp up the skin. Move the chicken around from time to time to ensure it cooks evenly. The skin should be hard to the touch.
Flip the chicken, then cook for about another 10 minutes, until the chicken is cooked through. Remove from pan.
Add the garlic and onion, stirring until onions are translucent. Stir in the tomatoes and spinach until the spinach is wilted.
Add the heavy cream, salt, pepper, and nutmeg bringing to a boil.
Add the Parmesan cheese and parsley, stirring until the sauce has thickened slightly.
Place the chicken back in the pan, spooning the sauce on top of the chicken.