For the sauce:
4 tablespoons butter
1 large yellow onion, chopped
4 cloves garlic, chopped
1 cup ketchup
3 tablespoons tomato paste
12-ounce can Dr Pepper soda (about 1 3/4 cups)
1/2 cup cider vinegar
1/3 cup Worcestershire sauce
1/2 cup packed brown sugar
2 teaspoons ground ancho chili powder or New Mexican chili powder
1 teaspoon white pepper
1 teaspoon kosher salt
For the tenderloins:
2 pork tenderloins (1 1/3 pounds each)
Freshly cracked black pepper or your favorite barbecue rub
In a heavy saucepan over medium-high heat, melt the butter. Add the onion and garlic and saute until translucent, about 10 minutes. Add the remaining sauce ingredients and simmer for about 15 minutes. Continue cooking until the sauce begins to thicken, about another 20 to 30 minutes. Taste and adjust seasonings with salt and pepper.
Let the sauce cool for about 10 minutes, or until it is warm but no longer hot. Using an immersion or traditional blender, puree the sauce. Let cool and, if not using immediately, pour into a clean glass jar. The sauce can be made in advance and refrigerated for 2 weeks.
To grill the pork, heat the grill to medium.
Wrap the tenderloins in paper towels to remove any surface moisture. This will help you to get great grill marks. Brush the dry meat with olive oil, then season with salt and pepper. Place the meat directly over the heat to sear. Grill for 2 to 3 minutes, turning once or twice, or until you get good grill marks.
Switch to medium indirect heat and move the meat to the center of the cooking grate and cook for 30 to 35 minutes total, turning once during cooking and brushing with the barbecue sauce every 5 to 7 minutes until the tenderloins are done and the sauce has created a glaze. Using a meat thermometer, make sure the tenderloins read 145 F at the thickest part.
Remove the tenderloins from the grill, allow them to rest for 5 to 10 minutes, then slice on the bias.
Nutrition information per serving (values are rounded to the nearest whole number): 470 calories; 130 calories from fat (28 percent of total calories); 14 g fat (7 g saturated; 0 g trans fats); 145 mg cholesterol; 43 g carbohydrate; 42 g protein; 1 g fiber; 1,220 mg sodium.
Photo: Mathew Meade