1 (1 lb.) pork tenderloin
Salt and pepper
2 tbsp. butter
1 tbsp. minced fresh sage or 1 tsp. dried (crumbled)
1/2 c. dry white wine
3 oz. Swiss cheese, cut into 6 slices
4 tsp. Dijon mustard
1/2 c. half and half

Season pork lightly with salt and pepper. Melt butter in a heavy skillet over medium heat. Stir in the sage. Add pork and brown well on all sides. Add white wine. Reduce heat to low, cover and cook until thermometer inserted in thickest part of meat registers 170 degrees (30-40 minutes). Remove pork from skillet. Cut 6 lengthwise slits in top of pork (2 rows of 3 slits).

Spread each cheese slice with 1/2 teaspoon mustard. Insert cheese into slits. Return pork to skillet. Cover and cook over medium heat until cheese melts about 5 minutes. Transfer pork to cutting board and cover with foil.

Blend remaining 1 teaspoon mustard into juices in a skillet. Add half and half and boil until slightly thickened, stirring occasionally, about 10 minutes. Cut pork into 1 inch slices. Arrange on plates. Spoon sauce over and serve.