In medium bowl, whisk together mayonnaise, yogurt, orange-juice concentrate, lemon juice, ginger, sugar, garlic, and salt. Cover with plastic wrap, and refrigerate for 15 minutes (or up to 3 days). Makes 2/3 cup orange sauce.
In large saucepan fitted with steamer basket, heat 1 inch of water to boiling. Place broccoli florets and stems in basket; cover. Reduce heat to medium-low, and steam 5 minutes. Serve with orange sauce.