Mix cornstarch and vinegar until blended.
Use vegetable peeler to cut 5 strips of peel from orange; place strips in large saucepan. Cut orange in half; squeeze juice over orange strips. Add dressing, ketchup, sugar, chili-garlic sauce and cornstarch mixture; mix well. Bring just to boil on medium heat; simmer on medium-low heat 3 min., stirring frequently.
Add cauliflower; stir. Cover; cook on medium heat 10 to 11 min. or until cauliflower is tender, uncovering and stirring occasionally after 5 min.
Meanwhile, microwave edamame in large microwaveable bowl on HIGH 2 min. Add rice; mix lightly.
Remove and discard orange peel strips from cauliflower mixture. Serve over rice mixture.