Wash the cabbage and cut about 3 inches down from the top to create a "lid."
Hollow out the inside of the "lid" piece. Carefully hollow out the center of the large cabbage base, leaving a wall about 4 layers thick. (Save the inner cabbage for another use).
Form your raw meatball mixture into large meatballs. Pack them into the hollowed-out cavity of the cabbage base.
In a bowl, whisk the tomato paste, olive oil, and your chosen seasonings. Gradually whisk in water until it reaches a pourable sauce consistency.
Pour the sauce generously over the meatballs inside the cabbage, and pour any remaining sauce into the bottom of the baking dish around the outside of the cabbage.
Place the cabbage "lid" securely back on top of the bowl.
Preheat oven to 400°F (200°C). Tightly seal the entire baking dish with heavy-duty aluminum foil to trap the steam.
Bake for 1.5 to 2 hours, depending on how tender you want the cabbage. Do not open the foil while baking.
Carefully remove the foil. Slice the cabbage into wedges and serve with the meatballs and sauce over a bed of white rice.