In a large mixing bowl, combine the ground lamb or beef, uncooked rice, finely chopped onion, minced garlic, chopped parsley, chopped dill, chopped mint, ground cumin, ground coriander, ground black pepper, salt, and vegetable oil. Mix well until all ingredients are evenly distributed.
If using jarred grape leaves, rinse them under cold water to remove excess brine and drain well. If using fresh grape leaves, blanch them in boiling water for about 2-3 minutes until tender, then drain and rinse under cold water.
Lay a grape leaf flat on a clean surface, shiny side down. Place about 1 tablespoon of the filling mixture near the stem end of the leaf.
Fold the sides of the leaf over the filling and roll it up tightly from the stem end to the tip, like a small cigar. Repeat with the remaining grape leaves and filling.
Arrange the rolled dolma seam-side down in a large pot, packing them closely together.
Pour the beef or vegetable broth and lemon juice over the dolma, ensuring they are mostly covered with liquid. If needed, add a little more broth or water to cover.
Place a heatproof plate on top of the dolma to keep them submerged in the liquid.
Bring the liquid to a gentle boil over medium heat. Reduce the heat to low, cover the pot, and simmer for about 45 minutes to 1 hour, or until the grape leaves are tender and the filling is cooked through.
Remove the dolma from the pot using a slotted spoon and arrange them on a serving platter.
Enjoy your meal!