Trim the silverskin from the pork tenderloin. Remove the pit and quarter the peach. Quarter the onion or slice it. Measure out the spices and bourbon.
Searing & Deglazing with Slow Cooker
Add enough oil to lightly cover the bottom of the pot. Combine the spices and rub all over the pork tenderloin. Cut the tenderloin in half if it won't fit in the pot whole to evenly sear.
When the oil is hot, but not smoking, place the tenderloin into the pot and sear on the one side for 2-3 minutes. Flip and repeat. Sear the ends if desired.
Add in the onions and the peaches. Pour in the bourbon while the pot is hot and deglaze the bottom. Scrape the fond off the bottom of the pot so it incorporates with the liquid. Simmer for about 5-7 minutes to burn off some of the alcohol.
Searing & Deglazing with Skillet
If your slow cooker can't sear, use a large skillet on the stove. Heat the pan and the oil over medium-high heat.
Combine the spices and rub it all over the pork tenderloin. Cut the tenderloin in half if it won't fit in the skillet whole. When the oil is hot, but not smoking, sear the tenderloin on all sides for about 2-3 minutes each side.
Add the peaches and onions to the skillet and pour in the bourbon to deglaze the pan. Scrape the bottom to release the fond into the liquid.
Transfer the contents of the skillet to your slow cooker. Make sure to get all the liquid.
Slow Cooking
Slow cook on high for 20-30 minutes. If you are using the Ninja Foodi make sure the pressure lid is on and the valve is vented.
Check the internal temperature and the pork is done when it is 145℉/63℃ or higher. At 30 minutes, I was into the 170℉ range. So, you might want to check it at 20 minutes. Keep in mind your slow cooker may function differently, so allow some extra time when making the recipe for the first time.
Remove the pork tenderloin and let it rest while making the sauce.
Making the Sauce
Make sure the liquid isn't too hot for your blender. Cool it down if necessary. Transfer the liquid, peaches and onions to a blender or a container if you are using an immersion circulator.
Blend on high speed until the sauce is smooth.
Serving
Pour some sauce onto your serving platter. Slice the tenderloin into ½-1" slices and lay them on the sauce. Garnish with chopped green onions and chopped parsley if desired. Pour a little more sauce on top or serve the sauce on the side.
NOTE: Nutritional Values includes using all of the sauce, but in my experience you will have extra. Turn the extra sauce into a delicious bourbon peach bbq sauce by adding 2 Tablespoons brown sugar, 2 Tablespoons apple cider vinegar, 1 teaspoon paprika, and ¼ teaspoon chipotle powder. Simmer until sauce reduces.