Place potato slices on a baking sheet coated with cooking spray. Bake at 400° for 15 minutes or until tender.
Coat a large nonstick skillet with cooking spray; add 1 teaspoon oil, and place over medium-high heat until hot. Add leeks, zucchini, and garlic; saute until tender. Combine sauteed vegetables, chopped basil, vinegar, and salt; toss lightly.
Wipe drippings from skillet with a paper towel. Add 1 teaspoon oil to skillet; place over medium heat until hot. Arrange potato slices in bottom of skillet. Cook over medium heat, without turning, 10 minutes or until potato is lightly browned. Spoon vegetable mixture over potato; sprinkle with cheese and pepper. Pour egg substitute over vegetable mixture. Cover and cook 15 minutes or until set. Cut into 4 wedges, and serve immediately. If desired, garnish with sour cream and basil sprigs.