This salad is full of potatoes, but very tasty and light - common home Turkish cooking, yet rarely served at restaurants. The recipe is from Ayla Algar's Complete book of Turkish Cooking. (Her books, if you don't mind the lack of photos, are among the best Turkish cookbooks). Her recipe does not have sumac, which I always add following my mum's method.
1/2 kilo potatoes
1 red onion
1/2 bunch of parsley or dill, chopped
1/2 cup olive oil (or less)
1/4 cup red wine vinegar
2 tablespoons lemon juice
1/2 teaspoon dry mustart
sea salt and black pepper, to taste
1 dozen black olives
1 tablespoon sumac
1. Half the onion lengthwise, then slice paper-thin. Rub with sumac.
2. Cook the potatoes in boiling water until tender. Peel and slice very thin into a salad bowl (I prefer dicing). Cool. stir in the onions, dill or parsley. (Alternatively, for a quicker version, wash, peel and rewash the potatoes. Dice them, and cook for five minutes in microwave oven set on high, covered and with a few tablespoons of water.)
3. Combine the oil with the vinegar, lemon juice, mustard, salt and pepper to taste. Blend well. Pour enough dressing over the salad to moisten; mix thoroughly. Adjust the salt and add more vinegar if necessary. Garnish with black olives. Serve at room temperature. 6 servings.
Note. Ayla Algar's book above is out of print. I had purchased mine on biblio.com. Her more recent book Classical Turkish Cooking is quite similar, and available on amazon.com.
Note2. I have recently come across with a very similar version by Bill Granger in one of the delicious. magazines. I suspect it was a slightly altered version of this Turkish salad.