Wash and pat dry chicken thigh pieces. Rub chicken thighs nicely with thick tomato paste and some spices like black pepper powder, oregano, parsley, salt, paprika, cumin powder, lemon juice, a few garlic cloves finely chopped, and olive oil. Mix all these ingredients nicely with the chicken thighs and keep this marinated for 30 minutes. Prepare the baking pan by pouring a good amount of olive oil and placing some sliced onions all over it creating a bed to place chicken pieces on top of it. Next, place chicken thighs on top of the onions. Tuck some sliced onions and tomatoes in between and top of the chicken pieces thighs. Sprinkle a layer of Mozerella cheese nicely all over it along with some sprinkles of oregano and black pepper powder. Preheat the oven at 350 degrees Fnheight and bake for around 38 minutes or until the top of it turns nicely golden brown in color.