Sauté the onions in the oil until slightly tender. Stir in the rice & cook 10 min.
Combine all of the other filling ingredients with the onions & rice. Cook another minute or two. Remove from heat. Let cool.
Lay one grape leaf on a flat work surface, shiny side down.
Place enough filling at the stem-end of the leaf, and spread it about three-quarters across the width of the leaf. The amount of filling should be about the size of your pinky, depending on the size of the leaf. Start rolling the leaf from the stem end upward (away from you), then fold each side of the leaf over the filling, and continue to roll upward. Fold firmly so the leaf won’t unravel during cooking. (NOTE: Don’t roll too tightly, however, because the rice will expand and the leaf could burst during cooking.)
Line the bottom of the pot with some lettuce leaves. (This is a trick my grandmother shared with me. It prevents the stuffed grape leaves from sticking to the bottom of the pot.)
Place rolled leaves in a large pot on top of the lettuce leaves. Sprinkle with a little oil & salt.
Add enough hot water to cover the rolled leaves. Place a dish on top of the grape leaves to keep them in place. You might want to add another weight, such as a small pot filled with water to place on top of the dish. This keeps the grape leaves submerged for even cooking.
Bring to a boil, then reduce heat to low and cook for 30-40 minutes until the rice is tender.
Remove from pot; chill; serve with lemon wedges.