Pork Tenderloin with Peppers

1 (1 lb.) pork tenderloin, cut into 1-i nch medallions
1/2 tsp. kosher salt
1/2 tsp. pepper
1 Tbsp. olive oil
1 1/2 tsp. chopped fresh rosemary, divided
4 canned anchovy fillets, drained and mashed
3 cloves garlic, sliced
1 red bell pepper, cut into strips
1 yellow pepper, cut into strips
2 tsp. balsamic vinegar

Heat a large skillet over medium-high heat. Sprinkle pork with salt & pepper. Add oil to skillet and swirl to coat. Add pork to skillet; cook for 5 minutes. Reduce heat to medium; turn pork over. Ad 1 tsp. rosemary, anchovies, garlic, and bell peppers; cook for 7 minutes or till peppers are tender and pork is done. Drizzle with vinegar and top with remaining rosemary.