Heat oven to 350°F. Sprinkle pork with 1/2 teaspoon of the chile powder and 1/4 teaspoon each salt and black pepper. Place in a roasting pan.
Cut potatoes into bite-size pieces and zucchini into 1-inch chunks; stir together with tomatoes and remaining chile powder. Spoon around pork.
Roast at 350°F for 1 hour and 5 minutes or until pork registers 155°F on an instant-read thermometer. Remove from oven and cover loosely with foil for 10 minutes before serving.
