Push saute button and wait until screen reads HOT on the Instant Pot. Add oil, onion and ground beef. Cook until brown.
Deglaze bottom of pot by adding ½ cup of the recipe water to boil/scrape off stuck on bits. This will prevent a burn error during pressure cooking.
Add noodles and seasoning, do not stir. Allow noodles to rest on top of meat. This will help pasta cook but not burn on bottom as it expands with the tomato sauce.
Add tomato sauce and diced tomatoes on top of pasta. Do not stir.
Add water over top of the pasta. Do not stir.
Close lid and turn knob to sealing position. Pressure cook on high for 4 minutes (*6 minute cook time for gluten free noodles). Quick release pressure when cook time is done by turning the knob to venting position.
Stir and enjoy!