Peel roughly 3lb. potatoes, rinse, cut into half or quarters.
In an Instant Pot ( or pressure cooker ) insert, add quartered potatoes, and 1½ cups water to the bottom.
Place a folded trivet on top of the potatoes. This will help stabilize the meatloaf and allow steam to circulate. Do not open and extend the arms unless it can fit.
Crush crackers between hands and add to a large mixing bowl. OPTIONAL TIP: To make it super moist, add ½ cup to the bowl and soak the crumb for a few minutes, then drain and add the moist crumbs to the bowl.
Add grated cheese, onion powder, garlic powder, salt, pepper, parsley, red pepper flakes, soy sauce, ½ cup ketchup, and eggs to mixing bowl. Whisk to combine.
Add ground beef. Using your hands, work the mixture throughout the beef; set aside.
Put into mini loaf aluminum tins OR make a foil loaf pan by cutting two large heavy-duty aluminum foil sheets. Crisscross the sheet in the middle so one is horizontal and one is vertical.
Dump the meat into the center of the foil. Gently shape into a rectangle. Press the meat down and out to work it into a shape that will fit into your pressure cooker. Lift the corners up and lift it into the pressure cooker to see how it fits then reshape and repeat the process until it fits.
Roll the foil into thick bands bringing the ends to the meat corners then fold the corners in like you're wrapping a present. Basically, make a pan with sides to fit around the shaped meat.
Place meatloaf on the trivet. Ensure enough space is around the edges of the insert and meatloaf to allow steam to circulate. Meatloaf may appear to be above "max fill line" but that only applies to liquids so no need to worry.
Brush roughly ½ cup ketchup (more or less as desired) over the top of the meatloaf.
Turn the device on. Secure lid. Set the pressure valve to SEALING. Select MANUAL or PRESSURE COOK; cook on high pressure for 35 minutes. The pressure cooker will beep and indicate “ON” while it comes to pressure. It took mine about 15 minutes to come to pressure then it started to count down from 35 minutes.
Once done, select CANCEL. Do a QUICK-RELEASE (QR) by turning the steam release handle to release steam immediately. Once pressure pin drops, open lid and turn off the device.
Using a turkey baster or spoon, remove liquid from the foil packet into a cup or sink.
Lift and remove foil packet to the countertop.
Remove trivet. Drain potatoes. Place in a large mixing bowl with mashed potato ingredients. Stir and mix until smooth.
Cut meatloaf and serve or broil meatloaf on high for 5 minutes in the oven.