Arrange carrot in a vegetable steamer over boiling water. Cover; steam 2 to 3 minutes or until crisp-tender. Transfer carrot to a serving bowl, and keep warm.
Combine cornstarch and lemon juice in a small saucepan, stirring until smooth. Add water, and cook over medium heat, stirring constantly, until thickened.
Stir in margarine and next 3 ingredients. Cook, stirring constantly, until margarine melts. Pour lemon juice mixture over carrot, and toss gently.