Cut tenderloin lengthwise in half; cut each half crosswise into thin slices. Toss pork with 1 tablespoon oil, salt and, if desired, pepper flakes. Cook pasta according to package directions.
Place a large nonstick skillet over medium-high heat. Add half of the pork; stir-fry 2-3 minutes or just until browned. Remove from pan; repeat with remaining pork.
Stir-fry snap peas and red pepper in remaining oil 2-3 minutes or just until crisp-tender. Stir in marmalade, teriyaki sauce, brown sugar and garlic; cook 1-2 minutes longer. Return pork to pan and add mango and cashews; heat through, stirring to combine. Serve with pasta.