Set instant pot to saute on high, add butter, oil, onion and carrots
Saute until soft and golden, stirring occasionally for about 4-5 minutes
Add minced garlic and oregano, stir and cook about 1 minute or until fragrant
Add salt and pepper to chicken, set aside
Rinse rice well, add to pot
Clean and slice mushrooms, add to pot
Pour chicken broth into pot covering rice and vegetables, add more broth if needed
Place chicken breasts on top of rice mixture
Cover and cook on manual high pressure for 10 minutes
When done, allow instant pot to naturally release pressure
Remove lid, remove chicken and shred into bite size pieces
Stir in ¼ cup chopped parsley, peas and chicken
Serve immediately with parmesan cheese and parsley if desired