In a mixing bowl, combine the olive oil, shallot, Ellenos yogurt, chives, dill, white wine vinegar, and dried garlic flakes or garlic powder. Mix well. Season to taste with salt and pepper.
Add the cucumber to the yogurt mixture and gently mix until the cucumber slices are fully coated in the dressing.
Cover and chill for 1 hour. When ready to serve, transfer the salad to a serving bowl and garnish with the remaining herbs.
