Place the beans in a large pot, add cold water to cover by at least 4-inches and bring to a boil. Remove from the heat, drain and cover with fresh cold water. 

Add the onion, salt and bay leaf and bring to a boil. Reduce the heat and simmer for 30 minutes or until the beans are almost tender but still firm. They will be about half-cooked. Drain the beans and discard the onion and bay leaves.

In a Dutch oven or large skillet set over medium-high heat, add the oil and when it is hot sauté the fennel and onion until soft, about 3-4 minutes. Add the lemon juice and stir in the drained beans. Remove from the heat and set aside.

In a food processor, pulse the fennel, onion and scallions until finely chopped. 

In a large bowl, combine the ground meat, the onion-fennel mixture, tomato paste, rice, Aleppo pepper or red pepper flakes, salt and pepper. 

Mix until well combined. Set aside while preparing the grape leaves.

Fill a large pot with water and bring to a boil over high heat.

Drain the liquid from the jar of preserved grape leaves and remove them from the jar. Unroll the leaves and drop them into the hot water.  Immediately turn the heat off. Let the leaves soak for 2-3 minutes, then drain them in a sieve and plunge them into a pan of cold water to cool them. 

Gently separate the leaves and spread them on paper towels to drain. If the leaves have stems, clip them off with kitchen scissors. You will need about 30 or 40 leaves for the stuffing. 

Spread the grape leaf flat, dull side up and place a portion (see #1 note) of the filling on the center of the leaf. Turn up the stem end of the leaf, covering the filling. 

Fold over each end to enclose the filling. Beginning again at the stem end, roll the grape leaf gently but firmly into a compact cylinder. The surface of the leaf will cling together to hold the grape leaf in shape.

Place the stuffed grape leaf, seam side down, on top of the beans, starting at the edge of the pot. Continue stuffing and rolling the remaining leaves, placing them snuggly next to each other and working to the center. 

Pour 2 cups of the broth, olive oil and lemon juice over the rolled grape leaves. The liquid should just barely cover the grape leaves. Set the pot over medium-high heat and bring to a boil. Cover the pot with its lid and reduce the heat to low. Simmer for 30 to 35 minutes until the filling is cooked through and the beans are tender. 

Transfer the meat filled grape leaves to a platter and cover to keep warm. With a slotted spoon, scoop out the beans into a serving bowl and cover to keep warm. There will be about 1-1/2 cups of sauce remaining in the cooking pot. If there is more, boil over high heat to reduce it; if there is less, add some stock and bring to a boil. Taste and adjust seasoning. Thicken the sauce by combining the cornstarch with the cold water and whisk into the sauce. 

To serve, place a portion of the beans on each plate, with 3 or 4 dolma arranged on top. Spoon some of the sauce over the top and garnish with fresh dill or mint.