Heat oven to 375°F. Soften pie crust as directed on box.
Meanwhile, in 10-inch nonstick skillet, heat oil over medium-high heat. Cook onion in oil 6 to 7 minutes, stirring frequently, until softened and beginning to caramelize slightly. Add bell pepper; cook 4 to 5 minutes longer or until tender. Add chicken and teriyaki sauce to skillet. Cook about 2 minutes longer or until sauce evaporates slightly and chicken is warmed through.
Unroll pie crust on ungreased cookie sheet. Place onion mixture on crust, leaving 1 1/2-inch border around edge. Fold edge of crust over filling, pleating crust as necessary. Sprinkle top with cheese.
Bake 20 to 25 minutes or until crust is dark golden brown and cheese is melted. Cool 5 minutes before serving.