Horizontally, cut turkey tenderloins in half to make two 1/2 inch steaks; set aside. Stir together apple juice, hoisin sauce, ginger, salt, and ground red pepper in a small bowl. Set aside.
In a large nonstick skillet, cook sweet pepper strips and onion wedges in hot oil over medium heat for 4-5 minutes or until nearly tender. Remove vegetables, reserving oil in skillet. Add turkey to oil in skillet. Cook about 4 minutes or until brown, turning once.
Return cooked vegetables to skillet. Add apple juice mixture. Bring to a boil. Reduce heat. Simmer, covered for 8-10 minutes or until turkey is done.
Using a slotted spoon, transfer turkey and vegetables to a serving platter. Keep liquid in skillet. Cover and keep warm.
Combine water and cornstarch; Add to liquid in skillet. Cook and stir until thickened and bubbly. Add apple. Cook uncovered, about 3 minutes more or just until apple is slightly softened. Spoon apple mixture over turkey and vegetables.