Preheat oven to 425 degrees F, then coat the inside of a 9"x9" baking pan with nonstick cooking spray.
In a small bowl, combine salt, cinnamon, cardamom & pepper.
In a large bowl, place the sweet potato slices & sprinkle them with just 1/2 teaspoon of the spice mixture & just 1 1/2 teaspoons of the oil, then toss to coat.
Arrange the sweet potato slices in a single layer in the prepared baking pan, then bake uncovered for 10 minutes.
Meanwhile, cut the pork tenderloin in half, then rub the remaining oil over the pork, before coating it with the remaining spice mixture.
Place the coated pork halves over the sweet potato slices & bake for 15 minutes.
Meanwhile, cut each apple into 8 wedges, & when the pork has baked for 15 minutes, turn the pork over & arrange the apples around the meat.
Bake another 15 minutes longer or until a meat thermometer reads 145 degrees F ~ That's my reading, but if you're a traditionalist, you'll want it to read 160 degrees F!