Boil potatoes in a large covered saucepan with potatoes covered with water by 2". Bring to a boil over high heat; reduce heat to simmer and cook until fork tender. Drain and set aside.
Heat oil in a large skillet over medium heat. Add chicken and pepper; cook until browned and no longer pink in the middle, about 7 minutes. Add reserved potatoes and seasoning to skillet; cook 2 to 3 minutes stirring frequently.
Combine the lettuce and vinegar in a large serving bowl; toss well. Add cooled chicken and potato mixture.
Serve warm.
Recipe courtesy of US Potato Board.