Begin by preparing the vine leaves: remove the stalks, wash them, and blanch in boiling water for 4-5 minutes. Drain and set aside. Rinse the rice thoroughly until the water runs clear, removing the starch. To prepare the filling, heat ⅓ cup of the olive oil in a non-stick pan, sauté the onions until they begin to brown, about 3-4 minutes. Stir in the tomato paste with a wooden spoon to release its flavors, then add the grated tomatoes and let the mixture boil and reduce for about 10 minutes. Incorporate the dried mint, cinnamon, salt, black pepper, parsley, half of the lemon juice, and the rice. Combine thoroughly before mixing into the raw minced pork.
To form the koupepia (dumplings), lay a vine leaf flat in your hand, place a spoonful of the pork and rice mixture near the stem end, and begin rolling by folding the sides inward and rolling from stem to tip, ensuring it's tightly sealed. If the leaf is large, fold it around the dumpling to secure.
Line the bottom of a large pot with spare vine leaves, then arrange the prepared koupepia (dumplings) in tight rows. When all are in, pour over the remaining olive oil and lemon juice, and add enough water to nearly cover the dumplings. Place an upside-down plate on top of the dumplings, weighing it down with a cup of water to prevent them from unfolding during cooking. Cook on a stove over medium heat until boiling, then reduce to a simmer and cook for 45-50 minutes, or until the rice is tender. Allow to cool slightly before serving.
Note: As the story goes, our grandmothers often had many mouths to feed and wrapped these quickly without much finesse, yet they remained deliciously unmatched.