Unroll dough into a 13- x 12-inch rectangle; cut into 4 rectangles. Set aside.
Combine egg substitute and next 3 ingredients; stir well with a wire whisk.
Coat a small nonstick skillet with cooking spray; place over medium-high heat until hot. Add mushrooms and green pepper; saute until tender. Add egg substitute mixture; cook over medium heat until mixture is firm but still moist, stirring occasionally.
Spoon one-fourth of egg substitute mixtureevenly over half of each rectangle; sprinkle evenly with cheese and cracked pepper. Top each with a tomato slice. Fold rectangles in half over mixture; press edges together with a fork. Coat with cooking spray. Place turnovers on a baking sheet coated with cooking spray. Bake at 375° for 15 minutes or until golden. Serve immediately.