Place each chicken breast in a plastic bag and pound flat (about 1/2 inch thick). Cut into thin strips.
In a shallow bowl, mix the flour and salt. In a medium bowl, whisk 1 cup of the ranch dressing with the milk, egg and Tabasco sauce.
Working in batches, dredge the chicken strips lightly in the flour, dip into the ranch batter, then coat with flour again and transfer to a sheet of wax paper.
Heat 3 tablespoons of the oil in a large nonstick skillet over medium-high heat until rippling hot. Add enough chicken strips to cover the bottom of the pan. Fry until golden and cooked through, about 3 minutes on each side. Transfer the chicken to a paper towellined plate. After the first batch, discard the oil, wipe the pan clean with a paper towel and heat another 3 tablespoons of oil. Fry the remaining strips, using fresh oil for each batch.
In a large bowl, toss the lettuce and tomatoes with the remaining 1/2 cup of ranch dressing, or to taste. Divide among 4 plates and top with the chicken strips.