To the bowl of a food processor add garlic, cilantro, 1 ½ tablespoon soy sauce, black pepper and pulse until the marinade is well blended but still has some texture.
Place pork tenderloin in a large ziploc bag. Pour the marinade over pork tenderloin and marinate in the fridge for 2-3 hours.
Preheat the oven to 360 F and line a medium size baking dish with a foil.
Heat 1 tablespoon of butter in a large non-stick pan and over a medium heat.
Remove the tenderloin from a zippered bag, slightly shake off the marinade, and sear the pork tenderloin on all sides until golden brown.
Transfer the pork to the baking dish and bake for 30 minutes or until internal temperature reaches 160 F. Remove from the oven and cover with foil.
Meanwhile, to the same pan, add peaches and cook until the peaches are browned on the sides, about 5 minutes.
Add balsamic vinegar to a pan with peaches and stir for 2-3 minutes. Remove the peaches to a plate and set aside.
Whisk in chicken broth, and the remaining 1 tablespoon of soy sauce, slightly increase the heat and cook for 2-4 minutes until the sauce thickens.
Remove sauce from the heat, adjust the salt and stir in 1 tablespoon of butter.
Thinly slice pork tenderloin and serve with peaches and a peach sauce.
Enjoy!