In a plastic bag combine flour, salt and pepper. Add chicken pieces and shake bag to coat evenly.
In a large skillet heat 2 tablespoons of the butter over medium heat until hot. Add coated chicken pieces and cook about 8 minutes or until chicken is tender and no longer pink, and coating is golden brown, stirring occasionally. Remove chicken from skillet and keep warm.
Heat remaining butter in the same skillet until hot. Add chili peppers, onion, and crushed red pepper. Cook and stir about 5 minutes or until tender but not brown, stirring up any browned bits. Add cream to the skillet and bring just to a low boil. Return chicken to skillet, and stir until combined. Simmer, uncovered, for 1 minute more or until sauce is slightly thickened.
Spoon the creamy chicken mixture over hot, cooked (and drained) fettuccine, then sprinkle with cheese.