Clean chicken and place in a large bowl. Slice the onions into thick slices and
separate into rings; add to the chicken. If using tomatoes, dice them and add to
chicken. Add the bottle of ketchup and the black pepper (at least 1 teaspoon is recommended).
This dish should be spicy, but you can use less without affecting the taste.
Marinate in the refrigerator for a minimum of 4 hours or overnight.
Heat oil; brown chicken on all sides, then place in a covered oven dish. Add
about 1/2 litre of water to the ketchup mixture, until you have a smooth, but not
thick, consistency. Pour over the chicken.
Bake at 325 degrees F for about 2 hours or until the chicken just falls off the bones.