Peel (if desired) and thinly slice the apples and sweet onion.

Place them in a large preheated skillet over medium heat along with 2 teaspoons olive oil, 1 tablespoon butter, ¼ teaspoon salt, and a pinch of pepper.

Cook, stirring occasionally for 7-10 minutes until the apples are lightly caramelized and the onions are translucent.

Remove from the skillet and keep warm.

Preheat oven to 350-degrees Fahrenheit.

In the same skillet over medium/high heat, sear the pork tenderloin on all sides until golden brown (approximately 3 minutes per side).

Meanwhile, add 1 cup of stock (chicken, beef, or vegetable) to a measuring cup along with ¼ teaspoon of ground cinnamon.

Once the pork is browned, remove it from the skillet and keep warm.

Reduce the heat under the skillet to medium/low and add the prepared stock to the pan, scraping up all the browned bits from the bottom of the skillet (deglazing). Cook, stirring occasionally, for 2-3 minutes.

Return the apples, onions, and pork tenderloin to the skillet with the stock, and spoon some of the sauce and apples over the pork.

Place the skillet into the preheated oven and cook for 50-55 minutes, or until an instant-read thermometer reaches 145-degrees in the thickest part of the meat.

Remove from the oven, cover, and allow the pork to rest for 10-15 minutes before slicing and serving.

To serve, spoon the sauce and apples over the pork and enjoy!