Bring a medium pot of salted water to a boil while you trim the scallions. Roughly chop three bunches, and mince the fourth. Add the larger portion of scallions to the water, and cook about 5 minutes, or until tender. Drain, reserving about 1/2 cup of the cooking liquid. Puree the cooked scallions in a blender, adding just enough of the cooking liquid to allow the machine to do its work. Mix the puree with the egg and soy, then gently stir in the flour until blended. Add pepper to taste, then the reserved minced scallions. Film a nonstick or well-seasoned skillet with oil, and turn the heat to medium-high. Drop the batter into the pan by the tablespoon or quarter cup, and cook about 2 minutes to a side, or until lightly browned. If necessary, the pancakes can be kept warm in a 200-degree oven for about 30 minutes.