I use homemade yogurt, it's pretty thick. If the yogurt seems watery to you, throw it on a sieve through a triple layer of gauze for 20-30 minutes, excess whey will drain. You can also use low-fat sour cream.
Add ground black pepper, garlic crushed through a press and Italian herbs to the yogurt.
Add lemon juice. And, if you want, a pinch of lemon zest.
Add soy sauce.
Mix everything until smooth for the sauce.
It can be poured into a jar and stored in the refrigerator for 2-3 days.
You can use this salad dressing for any vegetable salads.