Heat a large saute pan over medium heat. Add the oil and heat. Add the collard greens and saute until limp but with a bite. Season with salt and freshly ground pepper, cover, and set aside. Meanwhile, poach the eggs. Set aside a bowl of hot water. In a small saucepan, bring two cups water and the vinegar to a boil. Break 1 egg into a small cup and gently slide the egg into the water. Repeat with the remaining eggs. Poach until the whites are firm and translucent, 2 to 3 minutes. Transfer the egg to the bowl of hot water and repeat with the remaining eggs until all are cooked. Before serving, lightly dry off the eggs on a clean, dry kitchen bowl. Toast the slices of bread and reheat the collard greens. Make a bed of collard greens and place two eggs on top of the sauteed greens. Drizzle the bread with the olive oil and season with salt and pepper.