For sauce, in a small bowl stir together soy sauce, lemon juice, and sesame oil. Set aside.
Place a steamer basket in a 12-inch skillet. Add enough water to come just below bottom of basket. Bring to boiling. Place broccoli in steamer basket. Reduce heat to medium low. Cover and steam for 4 minutes. Add sweet peppers. Cover and steam for 3 to 4 minutes more or until vegetables are crisp-tender.
Transfer vegetables to a serving bowl. Drizzle sauce over vegetables; toss gently to coat. Makes 12 servings.