Place chicken in resealable food-storage plastic bag. In small bowl, beat garlic, lemon juice, peel, oil, Italian seasoning, salt and pepper with whisk until well mixed. Pour over chicken; seal bag. Refrigerate 30 to 60 minutes to marinate.
Heat oven to 425°F. Line cookie sheet with nonstick foil or parchment paper. Place chicken on cookie sheet in single layer; discard marinade.
Bake 10 minutes. Turn chicken; bake 5 to 10 minutes longer or until no longer pink in center.
Split baked biscuits. On bottom halves of biscuits, layer cheese, cucumber, tomato, chicken and olives. Cover with top halves of biscuits. Serve immediately.