How to Make It
Place the diced potato in a medium saucepan; cover with water, and bring to a boil. Cook 7 minutes or until tender. Drain and let cool.
Coat a large nonstick skillet with cooking spray; place over medium heat until hot. Add onion; sauté 6 minutes or until tender. Remove from heat, and set aside.
Combine 3 tablespoons of cheese, basil, and the next 5 ingredients (basil through eggs) in a medium bowl; stir in potato and onion. Wipe skillet with paper towels, and recoat with cooking spray. Place skillet over medium heat until hot. Add egg mixture, and cook 6 minutes or until almost set.
Wrap handle of skillet with foil, and broil 1 1/2 minutes. Top with remaining cheese, and broil for 30 seconds or until cheese melts. Drizzle vinegar over the frittata, and cut into 4 wedges. Serve warm.