In a food processor, pulse 1 cup fried onions until finely ground (should yield about ½ cup), set aside.
Set a 6-quart Instant Pot to saute; add olive oil.
When oil is hot, add onion. Cook, stirring occasionally, until softened, about 5 minutes.
Stir in garlic; cook 1 minute more. Press “Cancel” to stop cooking process. Let cool slightly.
In a medium bowl, add beef, cooked onion mixture, eggs, ground fried onions, panko, green onions, ketchup, mustard, salt, and pepper. Gently stir together until well combined, but not overmixed.
Transfer mixture into a 7 to 8” springform pan. Gently press mixture to fill pan without packing it too tightly.
Add 1/2 cup water to Instant Pot; place trivet in Instant Pot. Place springform pan on trivet inside Instant Pot.
Place top on Instant Pot; twist to seal and lock. Turn Steam Release Valve to “sealing.” Set Instant Pot to cook at High Pressure for 25 minutes.
After cooking is complete, let pressure release naturally for 10 minutes. After that, manually release the pressure by turning the Steam Release Valve to “venting.”
Carefully open Instant Pot lid to avoid dripping condensation on top of meatloaf. Carefully remove meatloaf from Instant Pot.
Preheat oven to Broil. Remove meatloaf from pan; place meatloaf on a baking sheet lined with aluminum foil.
In a small bowl, stir together ketchup, mustard, and molasses for topping. Spoon ketchup mixture on top of meatloaf; broil until glossy, about 5 minutes.
Garnish with green onions, and or fried onions, if desired.