Pork tenderloin is one of those items that you'll find on sale frequently at the grocery store. I stock up on it when I find it and we have it prepared in one of many ways once a week or so. Here is one of our favorite recipes. It came from www.delish.com.
1 Tbsp olive oil
1 1/4 lb pork tenderloin
14 shallots (peeled and halved lengthwise)
2 shallots (coarsely chopped for sauce)
1 (10 oz) jar all-fruit apricot jam
1/2 cup chicken broth
1/2 tsp sea salt
1 cup fresh or frozen cranberries
1 1/2 Tbsp red-wine vinegar
1/2 tsp freshly ground pepper
1/2 tsp Thyme
Preheat oven to 425 degrees. Heat oil in a large ovenproof skillet over medium-high heat until hot but not smoking. Add pork and halved shallots to skillet. Brown pork on all sides, turning occasionally, 6 - 8 minutes. Remove skillet from heat.
Brush pork in skillet with half the jam; drizzle 2 Tbsp broth over shallots. Transfer skillet to oven. Roast, turning shallots occasionally until an instant-read thermometer inserted into center of pork registers 155 degrees, 30 - 35 minutes.
Remove skillet from oven. Using tongs, transfer pork and shallots to a plate. Let rest (it will continue to cook; temperature should reach 160 degrees).
Place skillet over medium-high heat; add remaining chopped shallots. Sprinkle with salt; add remaining jam and 6 Tbsp broth. Deglaze skillet, scraping up browned bits with a wooden spoon; add cranberries, vinegar, and pepper. Cook, stirring, until berries are juicy, about 5 minutes. Stir in thyme.
Slice pork; divide among plates. Serve with cranberry pan sauce and shallots.