The first step is to quickly marinate the turkey. In a small bowl, mix together 2 tablespoons of olive oil, chopped rosemary, salt, pepper, and minced garlic.
In a large bowl, place the turkey tenderloin. Pour the marinate over the turkey and let it sit for 5-10 minutes. If you have more time, cover the bowl with plastic wrap and place in the refrigerator for up to 24 hours.
Place 1 tablespoon of olive oil in the bottom of the Instant Pot and set the Instant Pot to the saute function.
Place the turkey in the bottom of the pot and cook on each side for 4 minutes to slightly brown the meat.
Pour the chicken broth into the Instant Pot and cancel the "saute" function.
Close the lid and set the cooking time to 15 minutes on High pressure.
After 15 minutes, allow the Instant Pot to natural pressure release for 10 minutes. Quick release any of the remaining pressure.
Open lid of the Instant Pot, remove the turkey with a slotted spoon or tongs, place turkey on a plate, and cover with aluminum foil. Allow the turkey tenderloin to rest for 10 minutes. Slice and serve.