Heat oil in medium skillet. Fry potatoes and one teaspoon salt in oil until golden. Add red and green peppers and onion; cook 5 minutes. Spoon into a greased 13"x9" casserole dish and top with sausage. Mix together egg substitute, milk, flour, 1/2 teaspoon salt and pepper in mixing bowl. Pour egg mixture over potato mixture; sprinkle with cheese. Bake, uncovered, at 350 degrees for 30 minutes.