Once heated, add in oil, onion, jalapeno, and garlic. Saute for 2-3 minutes.
Turn Instant Pot OFF.
Add in stock and scrape up any browned bits on the bottom of the inner pot.
Add in seasonings and stir well. Add in rice and gently push down with a spoon to submerge in stock. Top with tomato sauce.
Place lid on the Instant Pot and be sure vent knob is pointed to sealed.
Cook on HIGH pressure for 3 minutes for long-grain white rice, and 22 minutes for long-grain brown rice.
Let pressure release naturally all the way.
Remove lid and fluff rice with a fork, while stirring in the tomato sauce.
Stir in butter if desired and serve.
This recipe works with both long-grain brown and white rice. The measurements remain the same regardless of which variety of rice you use, but the cook time will vary. White rice needs 3 minutes to cook, brown rice needs 22 minutes.
If you don't care for spicy foods, be sure to remove the seeds and ribs from inside the jalapeno and use half a small jalapeno instead of a full jalapeno. If you love spicy foods, keep half the seeds--but be warned, it will be spicy if you happen to get a spicy jalapeno. And of course, you can omit the jalapeno altogether, but I do find that when left out, the rice is nowhere near as flavorful.