Prepare a charcoal or gas grill for grilling over high heat, or turn 3 gas burners to high. Place the eggplants directly onto the coals or flame and grill, using tongs to turn them as the skin chars, until blackened all over. Set aside to cool. Alternatively, roast the eggplant in the oven. Preheat the oven to 400°F and line a baking sheet with aluminum foil. Pierce the eggplants in a few places with a sharp knife, place them on the prepared baking sheet and roast, turning every 5 minutes or so, until the skin is blistered and begins to crack all over. Set aside to cool. Slice the eggplants in half lengthwise and scoop out the flesh, transferring it directly to a strainer to allow the liquid to release. Meanwhile, in a medium bowl, combine the tomatoes with the chile peppers, if using, garlic, shallot, 1/2 cup parsley, 3 tablespoons oil, lemon juice, cumin, pepper and salt. Add the drained eggplant and mix together with a fork. Transfer the eggplant mixture to a serving bowl and drizzle with the remaining 3 tablespoons oil. Garnish with the remaining parsley and surround with the cucumber slices.