Sprinkle minced garlic with salt; crush with the flat side of a large knife to make a paste. Scrape into a leak-proof 1-cup jar. Add remaining ingredients, seal tightly, and shake to blend.
PREPARE THE SALAD:
Place the lettuce in a large salad bowl. Top with cucumber, tomatoes, dill and lemon zest. Just before serving, drizzle with desired amount of dressing and toss lightly. Sprinkle with feta and freshly ground pepper and serve at once.
Notes
If you are preparing this recipe as GLUTEN FREE, be sure to use water in the vinaigrette (or GF broth).
Use any leftover dressing on grilled fish or chicken.