Heat 2 teaspoons of oil in a heavy small skillet over medium heat. Crack the egg into the skillet. Sprinkle with salt and pepper. Cover and cook until the white is firm and the yolk is almost set, about 4 minutes. Season with salt.
Meanwhile, toast the bread until golden brown. Rub the garlic over the toast. Sprinkle with the Parmesan. Spoon the drained marinara sauce over the Parmesan. Top with the egg. Place the open-faced sandwich on a plate and serve.
Simple Tomato Sauce:
In a large casserole pot, heat oil over medium high heat. Add onion and garlic and saute until soft and translucent, about 2 minutes. Add celery and carrots and season with salt and pepper. Saute until all the vegetables are soft, about 5 minutes. Add tomatoes, basil, and bay leaves and simmer covered on low heat for 1 hour or until thick. Remove bay leaves and check for seasoning. If sauce still tastes acidic, add unsalted butter, 1 tablespoon at a time to round out the flavors. Add half the tomato sauce into the bowl of a food processor. Process until smooth. Continue with remaining tomato sauce. If not using all the sauce, allow it to cool completely and pour 250-300ml portions into freezer plastic bags. This will freeze up to 6 months.