Broccoli salad sans mayonnaise

Here's a modified broccoli salad recipe:

Broccoli
Cauliflower
Shredded carrots
Red onions
Crumbled walnuts

Dressing:
Yogurt
Dijon mustard
I'm not a huge fan of Dijon mustard, so I added just a tip of a teaspoon for a slight hint of Dijon taste.  Add mustard to taste.