I re-wrote the recipe the way I'll make it from the pictures above in case they are removed due to copyright law.
@Johnny West please feel free to make notes as to what you did/didn't do different. I guessed on onion amount.
Peaches can be substituted for cherries.
Recipe
2 Tbsp canola oil
2 pounds pork tenderloin or sirloin (cook longer)
1 tsp dried sage
3/4 tsp kosher or sea salt, divided
1/2 tsp ground black pepper, divided
1 (12 ounce) bag frozen sweet or tart cherries
3/4 cup vegetable or chicken stock
1 Tbsp balsamic vinegar
1 Tbsp maple syrup
Optional: add 1 cup 1/4 inch chopped onion
Preheat oven to 350 F.
Heat a large oven proof skillet over medium heat. Add oil. Season pork with half the salt and pepper. Sear the pork on each side 2-3 minutes until golden brown. Place in the oven and cook until internal temperature reaches 145 F, probably 15 or so minutes for a tenderloin. Place pork on cutting board, tent with foil, and let rest for 10 minutes, then slice into medallions.
Meanwhile, return skillet to medium heat and add onion (if using), cook until translucent, then add sage, remainder of salt and pepper, cherries, balsamic, maple syrup, and stock. Stir to combine. Bring to a simmer, reduce heat, stir and scrape bottom of skillet until cherries burst and mixture thickens and coats back of spoon. Taste and adjust seasoning. Serve.
I'll probably serve with a wild rice mix and a green vegetable.