Purée eggs in food processor or blender. Add yogurt, mayonnaise, green onion, dill, basil, Dijon mustard, salt, garlic powder and cayenne pepper; process until smooth. Cover and refrigerate until serving time.
Serve with vegetables (e.g. sweet pepper strips, celery or carrot sticks, cucumber slices, broccoli or cauliflower florets, cherry tomatoes and mushrooms), pita bread wedges or bread sticks.
Dip can be refrigerated for up to 3 days.
Preparation: 15 minutes