How to Make It
Preheat oven to 450°.
Sprinkle pork evenly with paprika, 1/4 teaspoon salt, pepper, and cumin. Heat a large skillet over medium-high heat. Add 1 tablespoon oil to pan; swirl to coat. Add pork to pan; cook 8 minutes, turning to brown on all sides.
Place potatoes on a baking sheet; drizzle with remaining 1 tablespoon oil. Bake at 450° for 10 minutes. Add pork to pan with potatoes; stir potatoes. Bake at 450° for 15 minutes or until potatoes are tender and a thermometer inserted into the thickest portion of the tenderloin registers 140°. Remove pan from oven. Sprinkle potatoes with 3/8 teaspoon salt. Let pork stand 5 minutes before cutting into slices.
Combine remaining 1/8 teaspoon salt, vinegar, honey, mustard, and thyme in a small saucepan; bring to a boil. Cook 3 minutes or until thickened. Add butter, stirring with a whisk until melted. Remove thyme sprigs; discard. Drizzle mustard mixture over potatoes. Serve with pork.