Place vegetable oil and minced garlic in a small microwave safe dish. Microwave on high for 1½ minutes. Remove and add soy sauce. Stir to combine.
Preheat the grill to high. Brush some oil on the grates.
Place whole eggplants on the grates and grill or roast for 12 to 15 minutes or until eggplant are brown and soft. Turn eggplant every now and then so that they brown evenly on all sides. Remove and allow them to cool slightly.
When eggplant are cool enough to handle, peel to remove the tough skin. Cut into bite size pieces and place on a dish.
Drizzle garlic soy sauce dressing over eggplant and garnish with sliced green onions.