Add the onion, garlic and carrot to the Instant Pot with 1/4 cup of the vegetable broth. Press "Saute" and cook the veggies for 5-6 minutes until softened and fragrant, stirring often.
Add the rice and the rest of the vegetable broth. Seal the lid and make sure the Vent Knob is turned to "Sealing". Press Pressure Cook and set the timer to 3 minutes. The Instant Pot will read "On" as it builds pressure. Once the pressure has built up, it will start the 3 minute timer.
After the timer goes off, allow the pressure to release naturally for 15 minutes (no need to touch anything).
After 15 minutes, move the Vent Knob to venting to make sure all pressure has been released, then carefully remove the lid.
Stir in the peas and corn. Place the lid back on, no need to seal, and let set for 3-4 minutes to heat the peas and corn.
Remove the lid and fluffy with a fork, breaking up any clumps then serve right away.