Prep the Ingredients: Ensure rice is cold and grains are separated. Prepare all vegetables and set aside.
Sauté Vegetables: Set the Instant Pot to 'Sauté' mode. Add sesame oil. Once hot, add onions, garlic, and bell pepper. Sauté until onions are translucent.
Add Frozen Vegetables: Stir in the frozen mixed vegetables and cook for an additional 2-3 minutes.
Push Vegetables Aside & Add Eggs: Push the vegetables to one side of the pot. Pour the beaten eggs into the other side. Let them sit for a few seconds and then scramble. Once cooked, mix the eggs with the vegetables.
Add Rice and Sauces: Add the day-old rice to the pot. Pour soy sauce and oyster sauce (if using) over the top. Stir well to ensure the rice and vegetables are well combined.
Pressure Cook: Close the Instant Pot lid, set to 'Manual' or 'Pressure Cook' mode, and adjust the cooking time to 4 minutes. Make sure the venting knob is set to 'Sealing'.
Quick Release & Serve: Once done, do a quick release of the pressure. Open the lid, fluff the fried rice with a fork, and stir in sliced green onions. Adjust salt and pepper to taste. Serve hot.