Preheat oven to 425 F. Lightly mist a small roasting pan or oven proof skillet with olive oil spray. Set aside.
In a small bowl, combine the cumin, cinnamon, salt, black pepper, allspice, garlic powder, and chipotle pepper.
Rub the pork evenly with the olive oil. Then rub evenly with the spice mixture until coated. Cover loosely with plastic wrap. Refrigerate for 15 min.
Meanwhile, in a small bowl, combine the splenda, garlic, and hot-pepper sauce. Whisk to mix. Set aside.
Set a large nonstick skillet over medium-high heat until it is hot enough for a spritz of water to sizzle on it. With an oven mitt, briefly remove the pan from the heat to lightly mist with olive oil spray. Place the pork in the pan. Cook for 1 minute per side, or until browned on all sides. Transfer to the prepared pan. With a basting brush, evenly coat the pork with the reserved splenda mixture.
Roast the tenderloin in the oven for 16-18 minutes, or until a thermometer inserted in the center reaches 160F and the juices run clear.
Remove from the oven. Cover the pork loosely with aluminum foil. Let stand for 10 minutes.
Transfer the pork to a cutting board. Holding the knife at a 45-degree angle, cut into thin slices. Serve immediately