1.
Combine sliced cucumbers and onions in a salad bowl; set aside.
2.
Combine yogurt, extra virgin olive oil, lemon juice, mustard, garlic, dill, parsley, salt and pepper in a jar fit with a lid; close the jar and shake it until everything is thoroughly combined.
3.
Check for consistency and add more olive oil to thin it out; add more yogurt to thicken it.
4.
Taste for seasonings and adjust accordingly.
5.
Drizzle salad dressing over cucumbers and onions; toss to coat.