Using a food processor, grind the walnuts, garlic, vinegar, spices and water until smooth.
Taste and adjust seasoning to you your liking. (The filling can be made up to three days ahead of time and placed in a airtight container in the refrigerator. This is one of those fillings that tastes better with time, plan on at least a couple hours ahead at least.
Cut the top off the eggplant, no need to peel them and cut them lengthwise into long strips about 1/4-1/2' thick.
Salt the eggplant slices and let stand for an hour.
press out the juice, rinse and pat dry (the salting takes away the bitterness of the eggplant)
Heat 2-3 Tablespoons of oil in a skillet to medium high heat.
Brown on both sides you want them brown but still floppy not crispy
Place on a paper towel to remove excess oil
spread a layer of filling on one side of each eggplant and roll up to enclose the filling inside.
Arrange on a platter and garnish with pomegranate seeds and thinly sliced onion