In a small bowl, add yogurt, water (if using Greek yogurt), vinegar, dill, garlic, onion powder, salt and pepper. Stir well and set aside.
In a large bowl, add savoy cabbage, corn and peas.
Pour dressing over vegetables, gently toss with tongs until combined.
Best served cold.
Notes
Make ahead: You can prepare savoy cabbage salad for up to 3 days ahead, if you refrigerate vegetables covered in a bowl and add dressing before serving.
Store: Refrigerate dressed salad in an airtight container for up to 48 hours.
Savoy Cabbage: You can even create this salad with a combination of savoy and red cabbage for extra color and flavor.
Corn: You can use canned, cooked, or even frozen (and thawed) corn.
Peas: Once again, feel free to use fresh or frozen. I wouldn't recommend canned.
Yogurt: You can use either plain natural yogurt or Greek yogurt (2%+ fat). If you use Greek yogurt, you'll need an extra couple of tablespoons of water or milk to thin it a little.
Vinegar: You can use white vinegar, white wine vinegar, or even apple cider vinegar.
Herbs and spices: Do not use dried dill. If you need to substitute the dill, then go for parsley instead. Green onion can be used for garnish.