To make sauce, squeeze shredded cucumber to remove liquid, leaving about 2/3 cup cucumber. Stir cucumber, yogurt, sour cream, chives, salt, pepper, and cayenne together. Taste, adjust seasonings and refrigerate.

Remove tendons from chicken tenders. Mix cornmeal, Old Bay, dry mustard, mace, and cayenne. Coat both sides of chicken with cornmeal mix. In a heavy 10-inch skillet, heat 1 1/2 tablespoons oil on medium-high heat and sauté the chicken for 3 minutes, shaking pan occasionally to keep chicken from sticking. Add 1/2 tablespoon oil, turn chicken and sauté 2-3 minutes more until cooked. Set chicken on paper towels and keep warm. Sauté remaining chicken, adding 1 tablespoon oil if necessary. Serve with crunchy cucumber sauce or lemon wedges.