Grill Chicken: Follow the Mediterranean Grilled Chicken recipe to grill chicken, let rest, and slice and set aside. This can be done a couple of days in advance. Or use leftover rotisserie chicken.
Prep Vinaigrette: Add dressing ingredients, olive oil, lemon juice, vinegar, salt, pepper, and oregano to a small bowl and whisk vigorously or a mason jar and seal and shake to emulsify.
Make Salad: Add lettuce, tomatoes, cucumbers, and olives to a large bowl and mix. Pour on vinaigrette and mix well, add tzatziki and mix well, and finish with the feta cheese.
Soften Tortillas: Place tortillas on a plate with a damp paper towel between the 2nd tortilla and on top. Microwave for 15 seconds to steam slightly to soften and make more pliable.
Add Filling and Wrap: Add 1 cup of the salad to the center of a tortilla and top with 1/4 of the sliced chicken. Fold in the sides of the tortilla towards the center and then fold up the bottom of the tortilla, tightly tucking it under the salad. While keeping the sides of the tortilla tucked in, roll up until a tightly wrap is formed. Repeat with the remaining tortillas. Use a very sharp knife and gently slice in half, if desired.
Enjoy!