Turn on Instant pot to the "Saute" setting and heat oil.
Add sausages and saute until golden brown.
Remove sausage to a cutting board and cut into thick slices. Keep aside.
Add onions, garlic and saute for about 1 minute.
Mix in sliced sausages, peppers, tomatoes, Italian seasoning, salt, pepper.
Pour water and mix everything together.
Put the lid on and turn up the the valve to "Sealing."
Select "Manual" mode and set the timer for 10 minutes.
When the cook time is over, turn the valve to "Venting" and let the pressure release.
Mix everything together gently. If the sauce is too thin, turn on the "Saute" setting and cook for 5-10 minutes until excess liquid evaporates and is reduced and the sauce becomes thick.
Garnish with fresh parsley, if you like and enjoy!
Notes
Read all my tips above.
Leftovers can be stored in a sealed container in the fridge for up to 3 days.